Friday Notes (Sep 24, 2021)

I skipped Friday Notes last month, and almost skipped it this month. To some extent that’s due to the note pile getting smaller, but the larger share of it is the exhaustion and ennui I’ve been feeling all year. My posts-per-month count has been noticeably down since April.

Over the 110 months of this blog (which doesn’t count 2017, the year I took off), the average is 10 posts per month, but in the previous two years it’s 14, so I do seem off my feed lately. OTOH, only 74 posts in 2018 (my lowest year), and I’m at 96 now, so there’s that.

In any event, here’s another edition of FN.

I’ve said this before; no doubt I’ll say it again: I really don’t like touchscreens. Years now of using them have made that pretty clear.

There is convenience in pocket computing, yes, but apps with a touch interface are so inadequate compared to what I’m used to. There’s no fine control, and forget about typing (let alone editing).

I’ve been especially aggravated trying to highlight text in books. It’s hard to get the text I want. The finger is a blunt instrument. And for some reason, it never seems to want to include the final period.

The lack of feedback is annoying, too. App designers aren’t always good at providing immediate visual or audible indication. Sometimes I’m not sure the app saw my touch or not. Sometimes they don’t, so I’m never sure. (The YouTube iOS app seems especially prone to ignoring touches.)

Sometimes when I’m idle I play that simple game, 2048, and I’ve messed up my chances a bunch of times by accidentally swiping because my finger was too close. That’s the other thing that drives me crazy about touchscreens — all the accidental activations. I moved the phone app to a second screen so I wouldn’t accidentally butt-dial.

And they’re always dirty.

§

There are many words, positive and negative, that sum up some aspect of how I react to life. Fascination is one of the positive ones. Hope is another. On the Yin side, I’d have to say a key one is disappointment.

I’m very disappointed we don’t act better. I know we can; there’s no question we’re capable of it. I see signs of it all the time. Our literature and art are filled with examples. And I see lots of people who do know how to act, but, as a friend of mine likes to say (with an implicit headshake), “Some people’s children!”

Anyway I got to thinking about, as a dystopic science fiction location, “The City of Dis” — dismay, disappointment, disenchantment, dissatisfaction, disgust, disgrace, disinterest, disaster, disease,… All dis bad stuff! Could fit in an allegorical or cyberpunk context.

But it sounded really familiar, like something Philip K. Dick had already written. In fact it goes back a bit further than that. The City of Dis is from the 1320 blockbuster bestseller, The Divine Comedy by Dante Alighieri. No wonder it sounded so familiar.

It would still make an awesome allegorical science fiction location. Blade Runner sort of thing, which is why it seems PKD must have used it, but a brief search only found Dante references (and a Boston rock band).

§

Sometimes I’m so slow. Every time I showered, I vaguely shook my head at the two large tags on the washcloth I use. It was a lot of tag for a washcloth.

Finally the lightbulb went on. Duh. Cut the tags off, dummy.

So now there’s fraying threads where the tags were. It gives me something else to shake my head at.

I think I may have been brainwashed by those tags that loudly tell you not to remove them under penalty of law! Somehow I never trusted the fine print that said it was okay for me to remove them.

§

Two movies I saw recently and recommend. (Neither inspire me towards their own blog post, but I enjoyed them.)

Flight (2012), starring Denzel Washington, directed by Robert Zemeckis. I’ve wanted to see this ever since I saw the trailers for it, but it never came around on the cable channels. Recently it showed up on Hulu.

It would be stretch to call it an anti-hero story, because Washington’s Captain “Whip” Whitaker is neither hero nor role model. Except for that time he saved a planeload of people despite being legally drunk sustained with cocaine.

It’s a masterful performance by Washington and worth seeing for it.

Bill & Ted Face the Music (2020), starring (of course) Keanu Reeves and Alex Winter. This is the third in the Bill & Ted series, and it comes after a 29 year gap. The first two were in 1989 and 1991. They’re all great goofy fun.

In the new one Bill & Ted are indeed much older, and they’ve failed to write the world-uniting song they were supposed to. In consequence, both their musical career and marriages are crashing. And so is time and space.

So they set off for the future to get the song from their future selves. (It doesn’t go well with their future selves.) Along the way they collect Jimi Hendrix, a young Louis Armstrong, Mozart, and Ling Lun, to play in their band. In the end, it’s their daughters — very close fallen apples — who save reality (and kinda steal the show).

A good serious time travel story is tough. Time travel is fundamentally an incoherent concept, so comedies are often the best genre for such stories (e.g. Back to the Future). The machines are fantasy anyway, so some stories don’t bother (e.g. A Connecticut Yankee in King Arthur’s Court). For something far more serious, Kindred, Octavia Butler’s “grin fantasy” (and her most popular work).

A rare serious SF movie that gets it right is the 2004 film Primer (but good luck following it without one). I’m also rather partial to the 2012 film Looper, which I also think gets it right…-ish.

§

Speaking of time, especially after reading Lee Smolin’s book, I think views of time fall into three+ categories:

1. Motor — time is fundamental; a source of change
2. Ratchet — time is an arrow insuring forward movement
3. Consequence — time emerges from something else
4. none of the above

I’m down for #1, and I know many support some version of #3. The second one isn’t as common. It’s something of a spin on #3, but posits time as something (other than entropy) that prevents physics going backwards. It is related to the view that entropy is time’s arrow. (Some versions of #3 posit that entropy is the source of time.)

Not going into any of that, I just like the triplet: Motor, Ratchet, Consequence.

I will say that Einstein’s notion of spacetime might have misled us a bit. We tend now to think of time as another dimension, but it’s really not. Reality works as if it were — it’s a very useful approximation — but time is quite distinct from the physical dimensions.

For one thing, we can’t change how we move in it. Our personal clock always ticks at one second per second. We certainly can’t stop or go backwards. Special Relativity does let us skip ahead relative to slower moving objects, but that’s just a shortcut nature allows. “I’ll speed up and meet you later!”

I think the spacetime interval itself singles out time from space:

$\displaystyle(\Delta{s})^2=(\Delta{x})^2+(\Delta{y})^2+(\Delta{z})^2-(\Delta{ct})^2$

The minus sign indicates that the time dimension is different. (The delta, Δ, just means change in. The ct gives us meters/second times seconds. The seconds cancel out leaving meters, which makes the time dimension a spatial one.)

There is a variation that puts minus signs in front of the spatial dimensions and a plus sign in front of the time dimension. The math is the same, up to a sign, and either way time is different from space.

Sometimes the interval is written:

$\displaystyle(\Delta{s})^2=(\Delta{x})^2+(\Delta{y})^2+(\Delta{z})^2+(\Delta{ict})^2$

And the ictsquared turns the i into -1, providing the minus sign. But it also brands time as an imaginary dimension, so again time is different from space.

Once spacetime is broken back into space and time, we’re free to accept time as fundamental (if we choose) and still have space be emergent (which is Smolin’s program).

§

Quite some time ago I wrote (and I paraphrase here):

The Theist problem: It might be false.
The Atheist problem: It might be true.

I think these are important and obvious truths, even for believers on either side. (I’m generally opposed to certitude, to gnosticism — I’m a decisive Agnostic.)

Likewise:

Anything not proven may be wrong.
Anything not disproven may be right.

And again I think these are important obvious truths. (Proving is harder than disproving, which is why falsification is a cornerstone of science. It’s really hard to prove something is true.)

§

I’ll end with the same topic I started with, my post count:

The year isn’t over, but the count is definitely down. (2017 is like a missing tooth.) I think this century is getting to me.

Stay timely (and tag-free), my friends! Go forth and spread beauty and light.

The canonical fool on the hill watching the sunset and the rotation of the planet and thinking what he imagines are large thoughts. View all posts by Wyrd Smythe

13 responses to “Friday Notes (Sep 24, 2021)”

• Wyrd Smythe

I’m not one for video games, not in decades, but 2048 seems to have captured me a bit. Simple to play, and with a strategy not very hard to get 2048. I win about half the time. Now I’m playing for high score and 4096 (which I’ve gotten about three times so far).

• Peter Morgan

I’d more say that, as mathematics, the spacetime interval singles out the forward and backward light cone.

I’ve never felt any of the things people say about time to be very compelling, but I can usually see why people say what they say. All of the above, perhaps, but not necessarily all at the same time and often just depending on which ideas I’ve heard most recently?

The experiential difference between the apparently remembered past and the apparently only guessable future perhaps seems too little acknowledged by just taking time to be a coordinate, but otherwise I’ve never felt that relatively dialed-back choice goes very far astray.

• Wyrd Smythe

Yeah, I can see that. It does in the sense that it divides answers into positive, negative, or zero values. And all observers agree about light cones, which is the part that seems most significant to me. All observers agree about spacetime intervals.

None of the things people say about time is compelling? 😀

I very much agree about the «now». I forget if I read it in Smolin’s book or Wilczek’s, but apparently Bohr said something about the wavefunction applying to the future, whereas the past is “collapsed” (whatever “collapsed” turns out to be). This view links the idea that the wavefunction embodies possibilities — possible futures — but the past has been measured and fixed.

Kind of an interesting way to look at it, I thought.

• Peter Morgan

Very compelling” is a high standard! Like I say, I can see why each position makes sense, to me as well as to their authors, but then I notice other aspects that are not quite well-enough accommodated, precisely because the other positions also make sense to me. Taking time to be a coordinate to some extent unifies your three, but also not enough for me to feel that it’s very compelling. Even apart from the not-true-enough-to-experience aspect, I think of time-as-a-coordinate as too instrumental for everyone to find it compelling, but if we’re going to measure the elapse of time and differences of position, I suppose we will describe the coordinates we use.

• Wyrd Smythe

Heh, yeah, that’s kind of what makes a conundrum a conundrum — both sides have strong arguments and weak ones. (It’s especially bad with social arguments that have zillions of degrees of freedom.) In this case what tips the scale for me is that I can’t see how time can emerge without existing in the first place, so emergent time arguments seem circular to me. (And, as a realist, I have a strong view there is a fact of the matter, plus something has to be axiomatic, and I see axiomatic time as the simplest view.) But that’s just my take on it.

One thing about coordinates: one wonders about the origin and negative values. If time is a coordinate, is there a zero time? As you say, we make relative measurements with an arbitrary origin (and arbitrary units — cesium atoms, really?). I think the poor fit even shows up in the question people sometimes ask: “Is time a dimension or a coordinate?” That always confused me, because a coordinate is a point along some dimension, and a dimension is measured in terms of coordinates. I take the question to be asking whether we move through time or time flows through us, but even so I’m not sure that’s a meaningful question.

FWIW, I’m also struck by how the proper time for every particle is the same: one second per second. That universality seems axiomatic to me. But that’s just my guess. 😉

• Peter Morgan

For me, the idea of a particle is problematic enough that I don’t think I could happily have it as part of any axiom.

For all practical purposes there are tables and chairs, but eventually they will break into parts and the proper times of the parts will start to diverge; there was also a time before the tables and chairs were crafted.

In a Lorentzian field theory, we can loosely think that at every point there’s a continuum of incoming causes, all coming from the backward light-cone; then into the future, there’s a continuum of outgoing what-have-you, which will be the grist of causes for future points in space-time. Or not, because of course the real world is apparently noisy, QM might be a more serious problem to such naive thinking than I think it is, and cetera.

At a large enough scale, the hundred-year existence of a chair is effectively a point, with the legs coming together within the past light-cone and with the broken pieces dispersing into the future light-cone. There are, I think, many causes for every event.

• Wyrd Smythe

It need not be down to the particle level, most atoms are stable and long-lived, and probably constitute their own frame of reference. I wouldn’t expect much gravity gradient in an atom, so GR wouldn’t apply, and while there are some high velocities, perhaps they cancel out so overall the atom can be viewed without SR? (I know most of the mass of the nucleons comes from the velocities of the gluons and quarks, but does the atom overall need SR?)

I quite agree with your tables and chairs. Once could, for instance, (in theory) trace the carbon atoms that become part of a tree, part of the lumber, part of the chair, part of a chair piece, part of the burned ash and on to whatever else it becomes part of. If that (and every other) carbon atom had a clock, it would always tick at one second per second (from the carbon atom’s point of view, obviously). That would be true of every atom ever created. (Some split or fuse, but the clock ticks on in the parts or aggregate.)

Also agree that each atom’s clock is unrelated to any other’s. They do indeed diverge. (I think it’s so cool that the center of the Earth has younger atoms from our point of view!)

Also also agree about light cones and many causes to an effect. Entanglement does raise questions. Bell experiments are annoying that way because there are frames where Alex measures first and frames where Blair measures first. Exactly what that means for the idea of axiomatic time may be above my pay grade. FWIW, my intuition is it’s not a deal-breaker, but perhaps I’m just naïve.

• SelfAwarePatterns

I like touchscreens on a phone or other small device, like a Kindle or iPad. I remember when the iPad first came out, a lot of people tried to turn them into laptops. I still remember one girl administering a Linux server from one, although she had a bluetooth keyboard to help. After a few months of experimentation, I never tried doing anything like that again. It’s a great device, as long as I use it only for consumption, not content creation, at least beyond short messages. But I do know people who write a lot of stuff on their phone. (Although one person I know who does that literally glues a separate keyboard to their touchscreen phone.)

The tags on washcloths can be handy if you want to remember which side you just used to wipe something gross.

I don’t have strong definite opinions on the ontology of time. I’m open to it being either fundamental or emergent from something, although the specific ideas I’ve seen pitched seem far from obviously right. (Not that I’ve done a lot of research in this area.) I’m seeing the idea of space being emergent from quantum entanglement come up more and more, but I’ve noticed that it’s usually space by itself, not spacetime.

On post counts, it seems like we all have our highs and lows. Your count is consistently higher than mine, except in 2017, and maybe 2014 when I posted almost every day.

• Wyrd Smythe

One of my friends has the email signature line “Tough typing on my iPhone!” so it appears at the bottom of every email. 😀 I did get a Bluetooth keyboard, and that makes chats tolerable. I have some California friends who’ve migrated from emails to chats over the years, so long-ish chat sessions is how we keep in touch now. I can’t do that without a keyboard; I don’t know how they can. (And, indeed, my message balloons are usually much bigger than theirs.)

I’ve said the same thing: great for consumption. I love carrying my music, photo, and e-book libraries around in my pocket, and the mobile internet access is great. But I was already into computers when the first IBMs and Apples came out, so I have larger ideas about what computers can do. You’d be in the same boat.

😀 Well, you’re supposed to wash your washcloths, you know…

Yeah, lotta people see space as emergent (Smolin does). One issue there is recovering our experience of 3D space. Why three orthogonal directions? Still, it seems possible to see how space is a consequence of the Big Bang, but it’s less obvious time must be. (Was there no “before” the BB?)

As I mentioned to Peter Morgan elsethread, the simplicity of axiomatic time, plus the universality of proper time, tips the scale for me. I’m also struck by Kant’s placing time as our most fundamental intuition.

The first two months of blogging I published 35 and 40 posts respectively! I’ve never come close to that again; my biggest month was March 2015 with 37 posts (due to the Special Relativity series). But then there’s 18 months with five or fewer, so, yeah, plenty of highs and lows. (No more so than in my first ten months where the counts were: 35,40,2,3,4,0,0,0,0,0. It was really choppy the following 10 months, too; burst months and dry months. I was somewhat more regular after that.)

• SelfAwarePatterns

Washing washcloths? Why wasn’t I made aware of this concept before now?!?

Good point on the orthogonal dimensions. Does anything about entanglement, in and of itself, entail that arrangement? If space is emergent from it, it seems like the dimensions would need to fall out somewhere.

It seems pretty common for a blogger’s most productive period to be the first few months of their blog’s existence, covering the range of our thoughts on whatever we’re blogging about. It’s ironic that that’s usually the period when we have the smallest audience. Although to some extent, that can be a benefit, as it’s typically a period when we’re still finding our writing voice.

• Wyrd Smythe

I dunno, man, it’s right there in the name. (The hard part for me was realizing I also had to wash stuff that didn’t explicitly say so, and I ran out of clean plates and shirts. So much to keep track of in modern life! I get so confused sometimes I brush my hair and comb my teeth.)

I don’t know of any property of entanglement from which the orthogonal directions of 3D space could emerge. Smolin said it was still an issue in LQG (which is a background-independent theory from which space emerges).

Smolin has a great analogy about cellphones that really illustrates the problem. He starts with a street (1D) where one has two neighbors, then opens it up to 2D with a neighbor across the street and across the alley (giving four neighbors), and then to an apartment building (3D) were one could have six neighbors in all six 3D orthogonal directions (and apparently no windows, just common walls). The point being the number of dimensions limits the number of immediate neighbors. You get two for every dimension.

In contrast a cellphone network allows connection between any two nodes. The number of immediate neighbors is the number of other cellphones. It’s effectively also the number of dimensions, so a cellphone network has a huge number of dimensions, and each dimension has a length of one. The problem is how this network can be pruned so each node has only six immediate neighbors. Smolin goes on to say that it’s not understood how to make that happen.

That makes sense, that bloggers would have a lot to say at first. Now that you say that, I’ve seen the same thing with music bands, filmmakers, and authors. In fact, long ago I kinda gave it a name, the Boston Syndrome. (A post that comes from my own “Boston Syndrome” period.) Heavy Metal magazine is an almost canonical example. A large market of untapped work from which they could take the cream. After a while they depended on what new cream came along… and a lot of milk. Milk is fine, but it ain’t cream. Early Heavy Metal was rich cream!

• SelfAwarePatterns

The cell phone network example is interesting, because we know it’s a higher level abstraction built on lower level ones (OSI layers), that eventually reduce to the physics of the 3D world. Space seems like more of an enabler and constrainer than something emergent. If it is emergent, we seem to be missing some layers. (Which of course might turn up tomorrow.)

On blogging and Boston Syndrome, yeah, the trick is figuring out how to revisit old themes but in a fresh way. I know I personally don’t like posting on a topic again unless there’s some new angle or aspect of it. Although I feel a little less inhibited if it’s been a long time (more than a year) since I touched on it.

• Wyrd Smythe

Yeah, if you look at what enables the cellphone network, it’s just 3D physics, so the metaphors do make it hard to see how space emerges without implicitly being there in the first place. (That sense is even stronger to me with time. All accounts of emergent time seem to need time to already exist.)

As I understand the relational theories, the links are primal. In some views the nodes are only vertices, only the links have properties. Since the assumption is space doesn’t exist, there’s no limit on every node linking to every other node. Reality (presumably because of the Big Bang) is just fully connected. (That would be a very low, even zero, entropy state, which accords with the need for entropy to be extremely low (or zero) at the start of things.)

But then, as we’ve been talking about, how to prune those connections such that 3D space emerges. And why 3D? (I have seen Penrose, I think it was, explore other possibilities, and many of them just don’t work. (I have suspicions about the coherence of rotation in higher dimensions.) It’s possible 3D is something of a sweet spot, but how does a fully connected network evolve into 3D is a question apparently no one has answered yet.)

Agree on both counts: fresh spins and length of time. My views often evolve, so the fresh spin part often happens in consequence. I have just flat out reposted “special occasion” posts (like the 9/11 one I just did), but any topic I return to I do try to move forward.

[I think our views on computationalism are probably largely unchanged — I assign a lower probability than you do — but my views on what computation is really have, especially in the last year. I’ve moved from a symbol-processing view to a dual-layer view that includes analog computers. (The bone of contention might be that under this definition, radios — and brains — still aren’t computers even though actual analog computers are. 😮 I swear I didn’t plan or intend it that way, and it’s irrelevant anyway. The truth of computationalism never depended on Brain≡Computer being true. Physical simulation doesn’t care.)]