Astrophysics

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The sun is the same in a relative way…but not as much as the CMB

Meet the new day; same as the old day.  Or at least, in everything but the trivial details, every new day is indistinguishable from the previous oodles of days.  It’s just a full rotation of the Earth around its axis, such that when it’s done, the same points on Earth are lined up with the same…

…well, okay, here there’s some variation depending on how you’re measuring the day.  There are solar days (our usual measure), which are reckoned when the same line of latitude points “directly” at the sun again.  But, of course, the Earth is moving relative to the sun, and at a noticeable rate:  it goes roughly one 365.25th of the way around the sun in one day, and so it takes slightly longer to get back to the original orientation toward the sun than it would otherwise.

Then there are sidereal days, in which we reset when the same point on Earth is aligned with the same relatively distant stars.  Such distance means the angular change to those stars caused by Earth’s motion is much smaller than the angular change to the sun.  So those day lengths are, I believe, more consistent, but they are actually slightly less than 24 hours long.

I suppose, at our current level of technology and understanding, the most consistent day measure would be Earth’s rotation relative to specific spots on the cosmic microwave background radiation, which would basically be as far away as anything we can measure.

The Milky way is moving slightly relative to the CMB though.  I think this is called proper motion*, but I may be misremembering that term.  Still, that rate of motion is tiny relative to the scales involved.  Although, come to think of it, since the Earth is moving within and along with the Milky Way, it’s possible that the Earth’s motion relative to the other, relatively distant stars within the galaxy may be smaller than its motion relative to the CMB.

I don’t know whether or not that is the case.  If anyone out there knows off the top of your head, I would be delighted if you would let me know.  But don’t bother Googling it, or asking some LLM about it; I can do that for myself if we’re going to resort to such tactics.

Speaking of relative motion and such, I did something relatively new yesterday afternoon with respect to reading.  Allow me to set the stage**.

I recently started dabbling (very inconsistently) in the online courses at MIT (and other universities) on their YouTube channel(s).  I started with Quantum Mechanics and then also started the General Relativity course, since I have some personal curiosities related to that subject that I’ve yet to see answered.

In the first lecture, the GR professor went over the main texts they would be using.  Well, I already have two of them, so I figured I would get the third.  I ordered it in paperback (the hardcover was ridiculously expensive, whereas the softcover was about the same price as any good-sized trade paperback).  After it arrived, it sat rather forlornly on my desk for some weeks.

oplus_34

Now, as I’ve said, I’ve been having a hard time reading fiction or nonfiction lately.  But a softcover textbook is no heavier than my lapcom would be, unlike the two hardcover GR texts I own.  So I brought the text General Relativity, by Wald, with me when I left the office yesterday.

The cool thing is, I actually read from it while waiting for the train and then while on the train.  I completed the preface/introduction and chapter one!  It’s not a long chapter, of course, and it mostly reviewed concepts of special relativity and so on***, which I know relatively (har) well.

Still, I feel reasonably pleased to have done this, and I hope to continue the process.  Maybe once I get this book under my belt, I’ll feel more inclined to do similarly with Sean Carroll’s Spacetime and Geometry, which is hardcover but not too terribly heavy.  Gravitation, on the other hand, is a book comparable in scale to Harrison’s, the “bible” of internal medicine.  It’s not a book one tends to carry around (though it provides its own rather pointed example of the effects of gravitation).

Anyway, with any luck, maybe I’ll inaugurate a more useful commuter reading schedule.  And maybe I’ll achieve enough skill at GR that I might be able to explore my perennial question.  At least, I should be able to learn more stuff, and that’s always a good thing.

I hope you all have a good day.

*Actually, no, in astronomy “proper motion” has to do with angular movement with respect to more distant stars, or something along those lines.  I don’t think it’s a great term for that.  The motion of a galaxy relative to the CMB is apparently called the “peculiar motion”, which seems like a rather peculiar choice to me.

**I don’t know how you could stop me even if you so wished.

***It has one practice problem, which is a version of the classic barn door paradox aka the ladder paradox, but I didn’t work the problem.  I know the basic answer already; it involves the relativity of simultaneity in special relativity, and the author asks us to draw a spacetime diagram demonstrating the basic issue.  I had no resources to do this on the train.

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“Every year is getting shorter; never seem to find the time…”

It is time, once again, for me to write another blog post‒though, actually, for you reading this, that time has already passed; for you, it is time to read another blog post.  That temporal disjunction is mildly interesting, and I have probably long since dwelt on it beyond the level of anyone’s but my own interest.

Still, it does illustrate some of the weird directionality of time, for while the time between when I write and when you read can be, in principle, limitless, it is always and only in one direction.  You will never read one of my blog posts so much as a single Planck time before I write it.

This is the character of causality, and its speed is the real speed limit that we narrowly think of as “the speed of light”.  It is actually the speed limit of causal influence, and that’s a fundamental part of the restrictions entailed in special relativity.

There is, though, the longstanding question of why time is not merely one-dimensional but unidirectional, since at local scales, the laws of physics don’t appear to have an inherent directionality but are time-symmetric.

Spatial dimensions don’t work that way.  You can go up or down, back or forth, left or right, however you please, with equal ease (don’t be a tease).  At least…you can do all that provided there are no strong influences nearby.

One such influence might be, for instance, a planet.  I just happen to have such a planet, right here.  It’s called Earth, and it is quite dense and so produces quite significant curvature of spacetime (time more than space, interestingly enough) in its vicinity.

This has the effect of making space asymmetric locally.

So, near a strongly gravitating object, space acquires directionality.  That directionality is actually spherical, so it’s not a simple kind of one-dimensional directionality, but in local regions it looks linearly directional.  Wherever you may be on Earth, odds are you can move any combination of left-right and forward-backward with equal ease (more or less).  But the difference between up and down is quite another matter.

That difference would be even more pronounced near a much stronger gravitational source.  If you were near the surface of a neutron star, your capacity to go any direction but down (i.e. toward the surface of the neutron star) would be more or less nonexistent.  Space would have a profound and irresistible directionality.  Things seem to become even more inevitably directional beneath the event horizon of a black hole.

And, analogously, when one is not far from a highly energetic, very low-entropy region of spacetime, like our Big Bang, time is forcibly constrained to be directional, since change can only really happen in the direction of lower entropy in such a region, as dictated by sheer mathematics, if nothing else.

I’ve written about this before, about how, in principle time could have more than one dimension, like space, but be so forcibly constrained by the very strong local effects of the Big Bang to be pseudo-linear, just as space is pseudo-planar at the surface of the Earth or a neutron star, with free movement in only two of its three dimensions.

I won’t get into it too much now; I think there are posts both here and on Iterations of Zero that address it.  I will just quickly point out that, in the distant future‒much like when one is much farther from the surface of a gravitating body‒as entropy approaches local maxima, time will lose its directionality and forward and backward will be identical.

The fact that it takes so long for that to happen may point toward the geometry of time being less than three dimensional.  Three dimensional influences fall off as the square of the distance.  So, twice as far from a source, the influence is one quarter as strong, and ten times as far away, it is one one hundredth as strong.

The directionality of time doesn’t seem to be falling off at any notable rate since the Big Bang*.  It doesn’t even seem to be falling off linearly, as would be the case for a two-dimensional process (the circumference of a circle increases linearly with the radius, whereas a sphere’s surface area increases as the square of the radius).  Based on a fairly straightforward interpretation of this, it does seem to point to time being one-dimensional.

But we don’t know the scale of the thing.  We may be, compared to the scope of any higher dimensionality of time, vanishingly close to the Big Bang, still.  We may be like tiny, tiny mites on Earth’s surface (or that of a neutron star), unable to sense or travel a significant height to be able to detect even the local curvature of the planet, let alone the drop-off in the directionality of space (i.e., gravity).

Maybe the nature of time is similar.  Maybe we are too small, moving through time too slowly, too close to its local source of directionality, to be able to discern that it has more dimensions.  Certainly, spacetime around us appears “flat” as best we can measure.  But we recognize that, at much bigger scales, it may be curved.  And time, at those scales, may have more than one dimension.

Or maybe:

Maybe if we can wait long enough, it will be obvious.  Or maybe not.

Have a good bit of time over these next 24 hours if you can, please.

*Though there is the current significant question of the nature of the “Hubble tension”.  Maybe it’s a subtle change in the strength of the directionality of time itself that leads to the seeming disparity in the Hubble “constant” when measured by CMB as opposed to by supernova data.  Hmmm.

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These our bloggers, as I foretold you, were all spirits and are melted into air, into thin air

Hello and good morning.  As you probably know, it is Thursday.  If you’re reading this later, however, I guess it might be useful for you to know that the 23rd of July in 2026 CE was a Thursday.  Maybe you’re an anthropologist or an archaeologist, and it’s a thousand years from now, or more.  If you’ve forgotten how to convert your year-numbering system to CE (AKA AD) then I am sorry, but I cannot help you.

Oh, wait, maybe I can:  the last time comet Halley passed through the inner solar system was 1986 CE, so 40 years ago from the year in which I write this.  Does that help?

Maybe you need a better description of comet Halley.  Well, it’s a big ball of ice and some rock, and when it gets close to the sun, the heat causes a lot of the ice to sublimate and become vaporous, and the vapor, which scatters light well, turns into a sort of aura and a “tail”, trailing away from the sun in a direction caused by the solar wind…

Oh, so you know what a comet is and looks like, you just want to know about this specific comet.  You want to know things to help you determine which comet it is so that you can get a clear guide to what I mean by “1986 CE/AD”.

Well, I can only tell you a little more than I already have.  It’s a short period comet, orbiting eccentrically (as comets tend to do) from well inside the Oort Cloud or even the Kuiper Belt*.  It is quite regular, as things in orbits that are not frequently significantly perturbed tend to be.  The period of its orbit is, if memory serves, about 76 years.  That ought to help you a lot, at least if you have astronomical records and keep track of such things at any level.

Years, of course, are a natural time increment, being the length of time it takes the Earth to go around the sun once “exactly”, returning to the precise spot in its orbit relative to the sun.  Mind you, the solar system, and the galaxy, and the local group, and all that other stuff are constantly moving, so in fact neither Earth nor comet Halley ever truly returns to where it was before.  But the solar system moves as a whole, more or less consistent in its internal motions despite the fact that its all orbiting the center of the Milky Way** about once every quarter billion years.

Of course, far enough in the future, the period of comet Halley will change, and eventually it will basically evaporate.  Also, the Earth’s orbital period will change over time (though much more slowly, since it is much more massive and its orbit less open to perturbation by other quite massive objects).

And, of course, in about five billion years‒about twenty turns ‘round the Milky Way‒the sun will become a red giant.  It won’t be like flipping a switch or something, where the sun is just the sun one day, 4,999,999,999 years and 364 days (or whatever) from now, then the next day, boom, it’ll swell up and devour the inner solar system.

No, it will be a pretty gradual process, for as the sun fuses more and more hydrogen, there will be proportionally less available, and the outward pressure caused by fusion will decrease, and so the the sun’s core will contract and it will get hotter so that helium will begin to fuse, but that won’t last nearly as long as the hydrogen did.

Also, as the core of the sun contracts and gets hotter, the outer portions of the sun will swell due to the increased heat within.  Well before the sun is a full-on red giant, its increasing temperature will have made conditions impossible on Earth for life as we know it.

But if you’re still around, five billion years from now, I hope your technological advances will make my help utterly irrelevant.  You might even have made the natural life cycle*** of the sun as much a matter of historical trivia as will presumably be the natural lifespan of an average modern human.

Anyway, by five billion years from now, you’ll be seeing the close-encounter/merger/collision of the Andromeda galaxy with the Milky Way, and that’s likely to be quite a spectacle.  That is, unless you’ve developed technology to intervene in that scenario.  It seems implausible, but five billion years is a long time for scientific and technological advancement.

In closing‒just in case you’re even farther in the future even than that and cosmic expansion has caused all but the local galaxy to pass over the cosmic horizon‒I want to tell you that this is not the only galaxy in the universe.  At the time of this writing, within the visible universe, there were between a hundred billion and a trillion extant galaxies.

But the universe, which “began” much more compactly, has been expanding since nearly 14 billion years ago, and if that expansion is continuously accelerating, as currently seems to be the case, the distance to all other galaxies will have eventually become too great and the recession too rapid for light ever to reach the Milky Way from any of them again.  But they did and do exist, even if there’s no trace left of them that you can see.

I thought you might like to know.

TTFN

*Do you need me to explain what these are?  Let me know.  Oh, wait, I’m in your past.  You can’t let me know without time travel (unless I’m still alive in your time), and if you had that, you wouldn’t need me to try to give you clues to the date system used in my time.

**Other candy bars are available.

***Other personal exercise devices are available.

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Is this blog good for MY mental health?

For the first time in quite a while, I’m using my mini lapcom to write this blog post.  The main reason for doing this is that my thumbs have really been bugging me lately.  Also, as I’ve often said, it feels more natural to type on the lapcom than on the smartphone, at least so far.  This shouldn’t be a surprise, since I have been typing far longer than I’ve been using a smartphone; indeed, I’ve been typing far, far longer than smartphones have existed.

How do you like them, Apple™?

Who knows, maybe someday I might get to the point where typing on the phone is at least as natural as on the lapcom.  I suppose if I wrote an entire book on one, that probably would make quite a bit of progress toward making it feel more natural.  But it isn’t as natural, and I don’t think it’s likely ever to be, at least for something like typing, because the scale is wrong; it’s too small*.  And of necessity, it either doesn’t have as many available functions as the desktop programs, or they are more difficult to access with any decent speed.

Okay, enough of that topic and/or subject.

I have, as you may know, been having somewhat worse than usual trouble lately with my chronic mood disorder(s).  I’ve been trying various personal interventions (nothing pharmacological at the moment), because it’s getting fairly bad and potentially very dangerous (to me).  Regarding those personal attempts, though, one thing I’ve noticed over time is a kind of internal barrier to certain specific interventions, and it’s kind of puzzling and a bit disturbing.

A long time ago—when our own galaxy was far, far away from where it is now**—I read a lot of various kinds of self-help and psychology books, trying to figure out, among other things, why I was so weird and how to get along despite that fact and such like.  In them, I learned about autosuggestion.  I also learned about a famous case of a proponent thereof who was ridiculed for encouraging people to try repeating to themselves on a few occasions throughout the day:  “Every day, in every way, I am getting better and better.”

Now, I’ve always thought that sounded quite interesting and potentially beneficial, especially since I tend to ruminate on and repeat things in my head anyway, and if I could make it something useful, then I might as well do so.  So, I applied it.

I never applied it in its original form, though.  I used to give myself messages about my mind getting stronger every day, or my will getting stronger, or my power (whatever that meant) growing, or me getting smarter, or me getting stronger in all senses of that word, those sorts of things.  But somehow, I always balked at telling myself that I was getting “better”.

I have tried doing the auto-suggestion thing again lately in various forms.  I think it at least gives me some mental focus, and at times at least makes me feel that maybe I’m getting stronger, or my will is improving, or whatever.  It’s a little silly but not without merit.  However, when I try to do the “better and better” version, it’s as if someone had cast one of those “langlock” jinxes on my mental tongue, and the phrase doesn’t want to come out.

It’s similar to the resistance I have to telling myself that “I love my life and I love myself”.

Interestingly, I was able to do that one while in prison, which feels sort of ironic, since I wasn’t loving life then.  But I knew that my situation was temporary—more so than life itself is, even—and I was able to keep looking forward to getting out and being part of my children’s lives again***.  Having something in the future toward which to look really helps keep your spirits up, or at least your fortitude.

I sometimes wonder if I fear getting better—not morally, I don’t think I have any issue with that.  But I do worry that some aspects of my personality could be quite harmful if I were to think too highly of myself.  I also have real internal revulsion (bordering on literal nausea) toward the idea of being delusional, especially about my own abilities and nature.

I guess it wouldn’t be too big a stretch to say that I fear it.  So many of the ills that I see in the world—current, past, and potentially in the future—are born of people who are too sure of themselves, too convinced they are right, too sure that they are exceptional, too convinced they know “better”.  I would hate to fall into such a banal and pathetic personality trap.  It’s all very silly, probably.  It might even make some of you laugh, or roll your eyes, or throw your hands up at my melodrama.

I suppose if I had anyone around with whom I could just talk about these things, I wouldn’t bother sharing them here on my blog.  They are, after all, quite personal.  But if I don’t share any of the thoughts I have, they are merely evanescent fluff inside my head that will never have any contact with other, external ideas, but merely have autologous impacts.  Of course, everything is like that (as far as we can tell), but I’d like to have some beneficial local impact on myself, at least.

And who knows, it may be possible, in the fullness of time, for the descendants of humanity, or similar beings, to break free of the nature of the transient and vanishing, and become, like the virtual particles near the event horizon of a black hole, real particles, things that endure indefinitely, and actually gain some degree of control over not only their own future but that of the universe itself.

When I’m being somewhat fanciful, I imagine myself contributing to such progress, and even being able to see it to its fruition.

See what I mean by getting egotistical?  I fear that tendency toward grandiosity, because it can be toxic all by itself, and because it is a frequent hallmark of more serious mental illness.  I’m more than a little afraid of that, because I often feel that manic magma of grandiosity rising up inside my mind.  I think it would be all too easy for me to lose my grip on myself entirely.  My mind, such as it is, is pretty much all that I have going for me; I’d rather not lose it if I can help it.

But the more time I spend on my own, the more likely it feels that it’s going to happen.  And I am not enthusiastic about it.

*That’s what she said.  Ha.  Ha.

**On a cosmic scale that doesn’t really mean anything, but time has passed, and the Earth, the Sun, the Milky Way, the local group, and so on are all moving.  From a cosmic scale they don’t seem to change much, but if you zoom in, even the surface of the Earth moves at nearly a thousand miles per hour (depending on your latitude) in its daily rotation alone.  Here’s The Galaxy Song to put it into context.

***It turns out that was overly optimistic and did not come to pass, but there was no good way for me to know this at the time.

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“The lone and level sands stretch far away.”

Welcome to July of 2026 (AD or CE) everyone.  Yes, since yesterday was the last day of June, then it must follow, as the day the previous day, that today is the 1st of July (given the specifications of “our” date-assigning system).

It’s payroll day today, of course, this being Wednesday.  I’m never too enthusiastic about such days.  I am, however, pleased to have learned that we, meaning those in my office, are not working this Saturday, it being Independence Day here in the US.  And we’re not working next Saturday, either, since it is a Saturday we would have had off, anyway.

That will be three Saturdays off in a row.  What will I do if I actually accrue a bit of rest and recover a bit of physiologic reserve?  Huh?  Have you ever thought about that?  Or are you too self-centered to be always and principally concerned about what is going on with me?

I’m kidding.  Even I don’t have much interest in my day to day life…or my life overall, now that you mention it.

Wait, you didn’t mention it; I mentioned it.  Then I projected my feelings onto you, whoever you may be that is reading this.  What pathetic, but very typical of human, behavior that is.

Obviously, I have nothing in mind about which to write today, despite having already written, let’s see…228 words.  I guess that’s not all that many words so far, is it?  Then again, it’s not very few words so far, either.

Speaking of “few” words, do please try to remember the difference between “fewer” and “less”.  If the referent of the adjective is something that comes in discrete, countable units, e.g., people or marbles or books, then the word to use is “fewer”, while if it is something that is continuous, such as some form of fluid or substance, e.g., water, air, sugar, then “less” is the word to use.  If you think* that it does not matter‒that it’s fine to say, “I have less friends than I used to have”**‒then try to realize that it’s just as bizarre as saying, “I’ve been drinking fewer water lately”, or “we only have a few sugar left in the sugar bowl”.

Even the Google Docs grammar checker balks at such uses of “few”, underlining them in blue as possibly incorrect, but it doesn’t highlight the “less friends” disgrace that precedes them.  This is what happens when these programs are “taught” their grammar simply through patterns of usage on‒of all the stupid things‒the internet, rather than by learning the logic behind grammar, and why it matters for clarity of communication.

There are arbitrary and unnecessary “rules” of grammar, of course, but they are fewer*** and farther between than you might expect.

I suppose it probably doesn’t matter, really, not on any kind of large scale.  Not unless it is possible‒allowed by nature, that is‒for humans or their descendants eventually to become cosmically important, to endure for eons, to engineer the shapes of galactic clusters and so on, and perhaps even to solve the problems of the “end” of the universe.

How’s that for a huge and noble quest:  to save the universe from the heat death/big crunch/big rip?  It’s crazily ambitious, but then again, only those who attempt the “impossible” can achieve the unbelievable.  I won’t say it’s the only way to make existence worthwhile‒such judgment is in the mind of each judge, and eternity is not a requirement to make a life a worthwhile thing (though the converse is also not necessarily true).

But for anything about any life to be remembered for any serious duration, then memory itself, conscious memory, must endure.  Simply stored records are not quite enough, not if one wants to leave anything behind that’s even as significant as “trunkless legs of stone” in the desert.

The universe itself seems unlikely to be finite in any larger sense‒the laws of nature that allowed our universe to exist at all seem likely to be, at some level, ever-present and “eternal” (though time is a function within the universe as we know it, so that “eternal” quality is not merely a function of time, but also of the very stuff of which space and time, and whatever else there may be, is made).

But one wants a universe where information from the past can persist, not merely be wiped away inevitably by the whips and scorns of time and big crunches and heat deaths.  If all one seeks is some time capsule that will never be opened, well, then you’re already making that, at least if the conservation of quantum information is correct, which most physicists who work in such areas seem to think it is.

Everything you are and do leaves evidence behind of itself and of you.  But so would a narrow, laser-based optical signal detailing all your thoughts‒something like a blog, say‒that you shine out into the widest void in space you can find, such that it will never so much as encounter a possible recipient before universal expansion has rendered such potential recipients too far away ever to be reached, even in principle.  Would that be satisfying?

I don’t know.  A lot of my writing hasn’t been too far from that situation.  But I do at least have readers here, whose minds become at least a little encoded (infected?) with the memes of my thoughts on a regular basis.  I can only apologize.

*And I use the word “think” here quite wrongly.

**No one should be surprised by your dearth of friends.

***See how weird it would be to think “they are less and farther between”?

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Cosmic. Way out. I can relate.

Well, here we are beginning another Monday, and I’m writing this post—again—on the mini lapcom.

I say “again” not because I am writing this very post for a second (or more) time, nor because the last post I did was written on the lapcom, because it was not.  I mean “again” in the sense that last Monday I wrote my blog post on the lapcom.  I also did so on Tuesday and on Wednesday last week, but I cannot yet say that I will do so tomorrow and the next day.  I won’t even say “barring the unforeseen”, because I can rather easily imagine, and therefore foresee, situations in which I will not write those blog posts on the lapcom.

Of course, I also cannot predict whether, like last week, I will write Thursday’s and Friday’s posts on the smartphone.  It’s not that unlikely, but I don’t know ahead of time whether I will write them on the smartphone or the lapcom.  I could make predictions, but I think anything deviating terribly far from 50/50 would probably be very much a rectally sourced prediction.

I will say, though, that if I do write blog posts the rest of the days this week—which will include Saturday, alas—I will almost certainly write them either on the lapcom or the smartphone.  How’s that for a bold prediction?  It’s not a certainty, of course, but then again, pretty much nothing is.  It’s getting into the high 90 percentiles though, I’d guess.  I’m not skilled enough at probability/decision theory to get much finer in my estimation than that.

Anyway, that was about 250 words of utterly pointless drivel, wasn’t it?  It’s quite odd how much and how quickly I can write about more or less nothing of significance.  Mind you, from a certain point of view, nothing is really of significance.  Also nothing is of significance.  I mean two different things by those two different uses of the same words.

The first means that there is almost nothing in the universe that, in itself, is significant (cosmically speaking, of course—on different scales, significance has different requirements).  No individual, localized thing or fact can matter much on the largest scales.  On the other hand, nothing—the vacuum, absence, whatever you want to call it—is significant.  This partly refers to the fact that the universe appears to be expanding at an accelerated rate, and this seems to be due to the vacuum energy, the energy of “empty” space.  A uniform energy density in space creates a negative pressure, which creates “negative gravity” in a sense, and that drives an expansion of spacetime.

The nature of this vacuum energy, or cosmological constant, is definitely significant in that it will determine, almost solely as far as we can tell, the future fate of the universe.

Of course, the term “vacuum” may be somewhat misleading given its ordinary usage (quite apart from when one refers to the household appliance).  The vacuum is never really “empty” despite what the usual meaning of the word is.  It’s full of all sorts of quantum fields as well as the gravitational field that is spacetime itself.  The vacuum is just when these fields are in their lowest possible states/energy levels*.

There’s also the famous Higgs Field, which actually is one of the quantum fields, but it is interesting in that it is a scalar field, meaning that it has magnitude at every point but not direction (like a map demonstrating local temperatures on Earth’s surface, as opposed to one detailing the wind, which will have magnitude and direction).

If this seems a peculiar distinction to you, think of the electromagnetic field, which has both magnitude and direction at every point.  It’s actually a little more complex even than just that, because of course, electricity and magnetism are two aspects of the electromagnetic field, but each one of them is a vector field (with magnitude and direction) which interacts with the other, so the combination of them is something more involved.

Also, when energies are high enough (changing the way the Higgs field interacts with other fields), the weak nuclear force and the electromagnetic force turn out to be part of the same thing, called the electroweak force.  And, of course, there is the question of whether all the fields are really just aspects of some “higher” field or structure.

This would be some form of “unified field theory” (not to be confused with GUTs, or “grand unified theories”, which are less grand and less unified than unified field theories).  Of course, we don’t know that there is a unified field.  There may not be.  There may just be a minimum number of fields that cannot be further reduced.

If M-theory (AKA string theory) is correct, then yes, there is a unified form from which all fields derive their character thanks to the shapes and resonances of their vibrations in high-dimensional spaces.  On the other hand, other versions of quantum gravity such as “loop quantum gravity” leave gravity (AKA spacetime itself) as a separate kind of field, composed of tiny, tiny parts (the “loops”) knitted together.

At least some versions of this theory have been disconfirmed, however, because it predicts a very, very slight difference in the speed of travel of electromagnetic waves depending on wavelength, and light from extremely distant quasars has been tested and found to be uniform in arrival time (based on variability in the quasars and specific catastrophic events, if memory serves) from wavelength the wavelength, even to tiny parts in billions of light years traveled.

Okay, well, that’s surely enough trivia for anyone early on a Monday morning.  I wish I didn’t have to work today, but then again, I wish I didn’t feel like I have to do anything.  But I do feel that way.  I guess it’s probably better than being inert.  Without a goal or goals—terminal, instrumental, or otherwise—there is no action.

You can call it a “drive” instead of a “goal” if you prefer.  That may be a more accurate term, since nature doesn’t act in a teleological way (outside of thinking minds) but instead generates drives/urges/impulses, some of which lead to increased genetic reproduction and some of which lead in the other direction.  Over time, the former are the ones that tend to accumulate, for what are probably obvious reasons.

Enough.  I already said it was enough, didn’t I?  Anyway, I hope you all have a good day.  And remember, if you tend to come to this blog via other social media, you can subscribe to it using your email, and then you’ll get emails sharing every new post with you directly.

Take care.

*There is also a thing called a false vacuum.  Spacetime itself could be in such a state, if the vacuum energy is capable of tunneling to an even lower energy level than the one at which it currently resides.  This would not be a good thing for the current inhabitants of the universe, but at least they would never know it if the drop-down happened, because everything that currently exists would be erased at the speed of light.  The universe as a whole would even be affected, but it wouldn’t be endangered per se.

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Should you give a fig about a freight train’s Newtons?

It’s Saturday, April 25th, in 2026 AD/CE.  There are only 7 shopping months until Newtonmas (Other holidays are available).

Anyway, I’m very groggy and tired today, though at least I am (for the moment) in slightly less pain than yesterday.  It still sucks, but now it’s more of a neutron star kind of sucking rather than a full scale black hole.

Not that either of those two stellar remnants can be said to “suck” in any atypical way, with respect to gravity.  It is true that the gravitation at the surface of a neutron star is extremely high (to say nothing of the “surface” of a black hole).  But that’s just because everything is so compact, and you can get much closer to the center of gravity than you would be able to do with more spread-out astronomical bodies made of more typical matter.

But, to reiterate a perhaps overused example, if the sun were suddenly (and without any other phenomena that would complicate the picture) to collapse* into a neutron star or even a black hole of the same mass, the Earth’s orbit would not change at all.

There’s no special “supergravity” or whatever some people imagine there might be due to black holes or neutron stars.  It’s just ordinary gravity with a large mass in a small region.  From farther away than the former surface of whatever collapsed into it, the gravity of a neutron star or a black hole is literally indistinguishable from that of the celestial object that became the black hole or neutron star (if it did not lose any mass in its collapse to the latter state, which in reality they almost always do).

How the hell did I get on that subject?  I don’t know.  I guess I’ll see it while editing.

I’m a little out of it this morning, because I took half a Benadryl last night in addition to my other, more typical stuff.  I don’t usually take Benadryl on a work night, but groggy and unpleasant quasi-consciousness that at least helps me to be unconscious is better than not being able even to get to sleep or stay that way for long and being groggy because of that rather than the side effects of an antihistamine.

Something like that, anyway; I’m not sure I made that very clear.

I’ve just now become briefly distracted because a redirected freight train just went by on the track in front of me (going south on the usually-northbound side of the tracks, something for which there were no doubt legitimate reasons, but which still feels quite wrong).  This happens occasionally, and I’m sure the process that leads up to it is somewhat interesting, at least from a certain point of view.

It’s definitely an event that happens only because something has gone wrong somewhere.  The tracks for commuter trains, like the course over which they run, are not really meant for heavy freight trains, so they can’t let them use them very often.  And it was heavy, I’m sure of that. There were numerous tank cars and box cars and all sorts of similar cars carrying potentially heavy stuff.  Even the train’s whistle as it approached was a different, lower pitched sound and had a more somber timbre (sombre timber?) than the usual Tri rail whistle.

I already was pretty sure it wasn’t a regular train when the nearby gates went down to stop traffic, because there’s no scheduled Tri rail train going in either direction at even close to that time on a Saturday.  If it were a behind-schedule train, it would have to have been the first train of the day going south, and it would be quite off its schedule indeed.  Trains only come every hour on the weekend.

I almost wrote “every hour on the hour” there, just for the “sound” of it, but of course it’s not feasible to have a commuter train arrive every hour on the hour at every train station unless the stations are an hour’s traveling distance apart.  That would be one hell of a commute, and not in a good way.

Anyway, I think that’s enough nonsense for today.  I still don’t feel good.  My legs and hips are still channeling low-level but constant DC current (or so it feels), and I am having more and more trouble seeing any point to continuing to try to style my way though all this.  It’s been more than 20 years and things are not improving overall.

It would be more tolerable if I had other people and reasons and points in my daily life, but I don’t, not really.  The comments here below this blog constitute the majority of my socialization, not counting work interactions (which are a different kind of thing, though related).

I’m so bloody tired.

Anyway, have a good weekend if you can.  For goodness sake, cherish the people you love and who love you, especially if you’re lucky enough to be with them every day.  And remember, when in doubt, don’t ask yourself “What would Newton do?”.  Unless you’re a scientist, that is, in which case, yeah, Newton was a decent role model.

Otherwise, he was a terribly unpleasant, vindictive, and spiteful man (and here I thought it impossible for me to admire him more than I already did).  He is reported to have laughed only once in his life, when someone asked him what was the point of studying Euclid.

I sympathize with Newton there.  That is an idiotic question for anyone who is stuck living in and making their way through three-dimensional, locally Euclidean space.

Mind you, when things like black holes and neutron stars are involved, you need to go beyond Euclid, but you can’t readily go beyond Euclid if you’ve never gotten to Euclid***.

*There’s no known process by which this could happen, by the way, so don’t worry about it.  Also, you don’t need to worry about encountering spherical cows or frictionless surfaces**.

**Though I’ve long thought that “Frictionless Cows” might be a good name for a band.

***You don’t need to read Euclid’s actual book to study Euclidean geometry, any more than you need to read Newton’s Principia Mathematica to learn Newtonian physics.  But it’s worth giving them each a tip of the hat in passing, at least, for they are among humanity’s greatest works.

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We have met the cosmic horror, and…

Well, here I go again (on my own, like the song says) writing another blog post.  As for why I am doing so, well, there is surely a set of causes‒potentially tracing all the way back to the Big Bang, or at least the period just during and/or after inflation, assuming that happened, which seems more likely than not‒there may not be any good reason for it.

Oh, of course, I could come up with reasons.  I could “justify” myself.  Indeed, there is reason (har) to think that justification and persuasion to bolster one’s status and identity in a tribe against others with opposed motives may have been one of the driving forces behind the development of the human reasoning capacity.  This is apart from, and perhaps almost orthogonal to, the basic power of reasoning to understand and thus best navigate the territory of reality.

Once it got started, reasoning would have accelerated thanks to biological arms races between those competing for survival and reproduction, and then it would have turned out serendipitously to have been more broadly and powerfully useful than merely for securing status and food and mates.

Imagine if the peacock’s tail had turned out not only to be ostentatious and beautiful and sexy (to peahens, anyway) but tremendously useful and broadly powerful, especially once it reached a certain level.  Imagine if the peacock’s tail had allowed peacocks to build skyscrapers and boats and trains and planes and cars, if peacocks’ tails helped peacocks build a global civilization, quite apart from their ability to secure one’s status and acquire good mates.

That’s quite possibly more or less what happened with human brains.

Of course, like the peacock’s tail, the human brain is not without its drawbacks.  I suspect that things like depression and anxiety, and perhaps even neurodivergence, are simply potential (and statistically inevitable) outcomes for a brain that has grown powerful enough to assess the world deeply and uncover the almost Lovecraftian terror of our tiny little existence when placed against the scope and scale of the cosmos.

I say “Lovecraftian”, but even with Lovecraft, though the beings in the mythos are thoroughly inhuman and incomprehensible‒unsane, as I like to say‒they are still beings.  The true cosmic horror is surely that beings of any kind are almost nonexistent; indeed, to a very good approximation, they are nonexistent.

In some senses, this can at least be morally reassuring.  If we do go and spread out through the universe‒or even just the galaxy or even just our local family of stars‒and there are indeed no other life forms, then at least we need not worry about violating implicit rights.  Uninhabited asteroids (for instance) don’t have goals or wishes and, as far as we can tell, they cannot suffer.

Of course, we may have aesthetic concerns about such things, but aesthetics are not as urgent as ethics.  And, of course, we will still have moral/ethical concerns toward each other; that almost goes without saying.

Whether or not we will exist long enough for the ethics (or lack thereof) of changing the state of uninhabited other places in the galaxy to be pertinent is quite uncertain.  I see nothing in the laws of physics that makes it impossible, so in that sense, I am optimistic.  But I see nothing in the laws of physics, nor more specifically in human nature, that makes it certain or even likely that we will survive to spread out from our native planet to any significant degree.  And I see nothing in the laws of nature that seems to imply that, if we don’t succeed and spread through the cosmos, anyone else will do so, or indeed that anyone else even exists.

Don’t get me wrong; physics clearly and undeniably allows life to exist, and it allows (human-like) intelligence and civilization to exist.  But those are two different scales of allowance.

The molecules and principles of life as we know it, with long-chain molecules capable of carrying information and of replicating themselves, leading to “competition” and “improvement” and increasing complexity and so on, seem so straightforward as to be happening potentially (but far from certainly) in a good many places in the universe.  This is straightforward enough.  The equivalents of viruses and prokaryotes may exist in many regions.  It’s even possible that there may be such life in other places in our solar system (Europa and Enceladus being possible contenders).

But multicellular, “eukaryotic” life, seems likely to be much rarer.  Basic life started on Earth, as far as we can see, very shortly after the Earth formed and cooled enough for complex molecules to endure (nearly 4 billion years ago).  Eukaryotes, especially multicellular ones, didn’t really arrive until about 500 million years ago.  So, seven eighths into the time of life on Earth, it was basically just “bacteria” and some viruses.

Then, for significant, interpersonal, symbolic and technological intelligence to develop took another…well, basically another 500 million years.  And as far as we can tell, it’s only happened once.

That doesn’t give us a good, clear picture of how rare or common such a thing is‒one is a difficult number of experimental subjects from which to draw too many conclusions‒but it’s possible that the existence of technologically intelligent life is so rare as to occur only once per, on average, every chunk of spacetime as large as our visible universe.  It could even be rarer than that.

In an infinite cosmos, of course, even such exceedingly rare events would happen an infinite number of times (so to speak).  But that doesn’t necessarily make things less lonesome.  If you have an infinite number of decks of cards (with no jokers), all thoroughly shuffled together, there are literally just as many Aces of Spades as there are red-suited cards in total (ℵ₀, the “smallest” infinity).  Nevertheless, if you draw cards randomly, you will only get an Ace of Spades one twenty-sixth as often as you will get a red-suited card.

Similarly, there are as many whole multiples of a trillion as there are integers in general (again, ℵ₀), but if you pick a random integer, you’re still only going to pull such a multiple one out of a trillion times (on average).

So, maybe the takeaway is that the real cosmic horror may be that we are the only entities haunting the abyss, and there are no (other) mad idiot gods bubbling away at the center of celestial existence.  Maybe it’s just us.  And if our lights go out, then nobody is home.

It’s worth considering, not least because it has every chance of being true, whether literally or just practically.  For if the nearest other technological life form is in another galactic cluster, for instance, then we are, for all reasonable purposes, alone in the universe.

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It’s the end of the week, but weakness persists

It’s Friday again, at last, and this is indeed the final day of the work week for me.  I am not expected to work tomorrow, and I think that even if they decided they were going to hold the office open tomorrow, I would not go in.  I am too tired and dispirited to once again throw myself into the gears of the machine just because other people want me to do it*.  Honestly, I feel it’s more likely that I’ll throw myself into real machinery than that I will go to work tomorrow.

Speaking of such throwing, as I was leaving the train yesterday evening, I found myself looking under the engine, seeing where the wheels meet the tracks, and wondering if I would have the guts just to lay my head across the track‒my neck, really‒and let myself be run over.  It would be a quick death, I suspect.

I don’t think I have the guts, though, not right now.  Also, it would be rude to screw up people’s commutes.  But it does carry a weird kind of perverse attraction.

Nothing else of interest is happening, really.  Well, perhaps one might concede that there are many interesting things happening, in the sense of the old curse, “may you live in interesting times”.  Unfortunately, even those types of interesting things that are happening are so…well, almost so trite, so pathetic, so contemptible, so predictable, so “been done already”.  None of the weird, would-be interesting, things that are happening are impressive in any sense.

Okay, well, I’ll concede the relative interest and impressiveness of the Artemis II trip around the Moon recently.  It would be more interesting if it hadn’t been something we’d done literally before I was born (3 months before, to the date, for Apollo 11’s landing), using computer systems that were‒to use the most conservative definition‒28 iterations of Moore’s Law ago.  So, literally, by more (ha) than one measure of that “law”, we are at least 2 to the 28th times as advanced, computationally, as we were when we first went to the moon.  That’s conservative, because I’ve heard descriptions of Moore’s Law that put the doubling time at 18 months, in which case there would be about 37 doubling times since then.

For those of you for whom exponentials don’t carry quite the visceral impact they ought to carry, 2 to the 28th power is 268,435,456.  So, by more conservative, every-two-year characterizations of Moore’s Law, our current computational powers are more than 268 million times what they were in 1969.  By less conservative estimates they are 137,438,953,472 times, so more than 137 billion times as advanced.

To be fair, it’s just computer tech that has advanced like that.  The process of engineering rockets hasn’t improved to the same degree, because that’s a large-scale engineering thing, and is more constrained by the rate at which one can directly interrogate nature and build and test technology.  Still, we went from Kitty Hawk to the Moon in about two thirds of a century, but in the more than half a century since, we’ve certainly not extended that streak much.

Okay, to be fair, we got pretty good at sending out space probes and such.  Even then, though, our most distant and still most impressive probes were launched in the late seventies.  There have been some quite impressive things since, and I intend no shade to be thrown at them.  That Pluto thing was very impressive, as are almost all of the Mars missions and the probes sent to other planets (on the other hand, the ISS isn’t that much more impressive than Skylab was).

The things that have improved significantly have largely done so solely because the increased capacity of computers has assisted in modeling and, well, computing things.  So, rocket science has improved to the degree that computer science has improved, divided by the fraction of that improvement that cannot make a difference in how well rockets can be made.  Something like that, anyway.

Yeah, rocket science hasn’t advanced much in my lifetime.  Brain surgery has done a bit better, but not as much better as one might have reasonably expected.

Then again, we’ve certainly improved our ability to make memes and now AI images and videos to make fun of people and express our own loyalties or outrages.  Yes, in a real sense, many of our greatest advances in recent decades have been improvements in our ability to hurl feces at each other like the monkeys we all are.  We appear to be more engaged by such shit-flinging even then we are by sex, which seems mind-boggling.

I say “we” but that broad description does not apply to everyone.  Some people are still more interested in sex.  At first glance, that would seem to be the more evolutionarily stable of the approaches, but it’s an empirical question, so we can really just wait and see which, if either, of the two tendencies prevails in the long run.

To paraphrase Dave Barry, I myself plan to be dead.

Anyway, that’s about all I have to say for this week.  I don’t mean to make a post tomorrow, but of course, as always, that is barring the unforeseen.

I hope you have a good weekend.

*Okay, to be fair, that’s not really the reason.  I do it because I get paid.

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It’s not about me. It’s not about you. It’s not even about everyone.

It’s Friday today (as I write this, anyway‒it may be another day entirely as you read it), and I am in the process of heading to work.  I will also be working tomorrow, barring (as ever) the unforeseen.  And that doesn’t just include the foreseen unforeseen; the unforeseen unforeseen (especially that one) can also change what happens tomorrow, in ways that we do not expect, more or less by definition.

Of course, the Tao te Ching advises us to act without expectation, and I suppose that’s pretty good advice.  The universe doesn’t make special deals, such that if you do some particular thing, it will definitely turn out the way you hope.  The universe does what it has always done, and you are not the subject or the object of its action‒you are just one of the innumerable things the universe does.  It did not have to ask your permission, and it will not apologize.  It also does not make exceptions, not as far as anyone can see.

 

Since the beginning

not one unusual thing

has ever happened*.

 

You can imagine and draw a map that looks any way you want, that contains fairy lands and misty mountains and roads that are shorter in one direction than another**, but if your map doesn’t match the actual territory, it’s not going to be useful for traveling through that territory safely and successfully (by whatever reasonable criteria you might judge success).  Likewise, blank spots on the map don’t imply blank spots in the territory, and writing “here be dragons” does not somehow conjure dragons into existence (alas).

Reality is that which actually exists, whether or not anyone “believes” it or “believes in it”, whether or not anyone has been, is now, or ever will be aware of it.  Heck, if eternal inflation and a consequent inflationary multiverse following (for instance) the string landscape are true, then the vast majority of the stuff of reality will never, ever be known, because most of it‒the ever-expanding inflaton field and those bubble universes where local laws are such that complexity cannot exist, as well as those huge stretches of even our universe that precede (or follow) any existence of life‒will never be accessible to conscious experience.

That’s okay.  Man is not the measure (nor the measurer) of all things.  Man is the measure of almost nothing.  Man‒indeed, all life of which we know‒is a tiny little epiphenomenon that exists in a tiny little sphere of nonzero thickness on and around the surface of the Earth.  I’ll try to remember to do the math comparing that volume to the volume of the visible universe and put it in a footnote below.  If it’s not there, I didn’t do it***.

One sometimes hears people say‒often they seem to be trying to make excuses for themselves to believe in some deity or other‒that the universe is exquisitely tuned for life, such that it requires explanation by some “supernatural” means.

When I hear or read such things, my reaction is, “What universe are you looking at?!?”  Almost no place in the universe can be survived by life as we know it, let alone produce it.  The fraction is so close to nonexistent that it is zero to a good first approximation, and a good second approximation, and a good third, and so on.

It may seem that time could possibly give us a bit more comfort than space does, since life on Earth has existed between roughly a fourth and a third of the time since our Big Bang.  But the future of this universe gives every indication of being without end, whereas conditions for large scale matter to exist‒as far as we can tell‒will not last long (not compared to infinity, which to be fair, nothing is, not even TREE(3) or Graham’s number or any other huge but finite numbers).

By the time the last supermassive black holes finish evaporating due to Hawking radiation, which will be about a googol years, things will already have been impossible for any kind of life we would recognize for eons of eons.

Of course, it’s conceivable that life will grow to become cosmically important and able to engineer specific ways for the universe to avoid heat death (or whatever is coming), or to make new universes, or whatever.  But that’s a mightily narrow course for the future to thread.

And the time until a straightforward Poincaré recurrence of the current state of our universe makes a googol years seem unnoticeably teensy by comparison.

Anyway, the main point I’m making, if there is one, is that the universe neither promises nor owes you anything.  That doesn’t mean it’s not okay for things to be important to you.  You matter (on the scales we’ve been considering) nearly as much as the whole Andromeda galaxy.

It’s fine for you to try to make your life what you want it to be.  Why not?  There’s no one else who has any legitimate claim to it (not counting children, friends, etc., all of whom could be considered part of “what you want it to be”).  Just don’t expect other people, let alone the vastly bigger number of things that are not people, to be also trying to make your life the way you want it to be.

Okay, that’ll do, pig.  I’m tired (What else is new?).  I’ll most likely write a post tomorrow.  I hope you have a good day.

*I got this haiku from Eliezer Yudkowsky’s Rationality: From AI to Zombies, though I am not sure if it originated with him.

**Actually, I’m not sure how you would draw that.

***I did it, though I initially made a mistake in calculating the surface area of the Earth, as you can see below if you look closely (I forgot to square pi in the denominator).  Anyway, assuming that the depth-to-height range of life on Earth is about 20 km, then the volume for life as we know it is about 1 x 10^19 cubic meters.  The volume of the visible universe on the other hand is 2.6 x 10^81 cubic meters (if my calculations are correct).  That means that the fraction of the universe that is, to our knowledge, amenable to life is 3.8 x 10^(-63), or 0.0000000000000000000000000000000000000000000000000000000000000038 of the volume of the universe.  By comparison, the fraction of your volume represented by one of your tens of trillions of cells is roughly 10^(-12), or .000000000001.  You lose thousands of cells every proverbial time you scratch your nose.  How much do you notice them?  How much less would the universe notice if it scratched all life off?