Time for Cause & Effect?

Cause, effect, and time are all mysteries at this point. As far as Physics is concerned.

When I was a young chicken, learning physics, pecking around the way chicken do, I came upon “the Arrow of Time”. At the time, the question about the nature of time was all about “Entropy” and the “Second Law of Thermodynamics”. How quaint it seems now that I got much wiser!

Entropy is about “states”. The “Second Law” says that processes augment the number of states, as time goes by.

The most basic question is then: ”What is a state?”

People in thermodynamics thought they had an answer. And, in a way, they do, like a car mechanics is full of answers about the state of your car.

Mechanics Getting Weirder: Are There Wormholes?

Mechanics Getting Weirder: Are There Wormholes?

[Yes, these distorted things are distant galaxies, viewed through the wormhole. The picture, from the excellent movie “Interstellar” depicts how a wormhole in spacetime would appear at close range; the little flower is the rotating spaceship. Interstellar represents an Earth where society has pursued its way down the abyss, thanks to the anti-science, anti-rationality movement in evidence nowadays. NASA went underground… Something not far removed from its present state, where tantalizing clues for life on Mars are left unexamined, because of the anti-nuclear movement… Long story, another time.]

However, nature is a Quantum car. And mechanics have nothing to say about it. Quantum Physics has its own notion of state. Moreover, in the meantime, the very notion of time and causality came under attack. From an unexpected corner.

It was simple enough when Lorentz and Poincaré introduced the notion of “local time”. Time was relative (Poincaré Relativity Principle, 1904): it depended upon one’s state of motion. In a local frame moving fast, time slows down (relative to the friend who did not get on that speedy rocket).

Einstein then observed that if a local time was accelerated, it would also slow down. Einstein somehow hoped to extract from this “General Theory of Relativity” a cause for inertia, but he failed (and could only fail, as GTR is local, not global). He ended up with just a Theory of Gravitation (Fock), a better and much improved version of the one of 1700, true… But still GTR is articulated basically the same equation arising from Ismael Bullialdus considerations in 1645 (and then Huygens, Borelli, Hooke, etc.)

Enter Quantum Physics. There time is absolute (oops). Locally absolute over an extent. Why? Because each Quantum processes are logically and mathematically analyzed in a particular space, relative to said process, and GLOBALLY therein (here is that global concept Einstein was desperately searching for, as he craved for inertia as a global phenomenon, following Newton and Mach).

That particular space relative to that particular process is not just two dimensional (as in the famed double slit experiment), it can be pretty much anything that can be depicted as a Hilbert space (consider Dirac Spinor space).

In the past, before 1904, one could consider that if something A preceded something else B, in time, A could have “caused” B. However local time already messes up with that situation (consider closed time loops in GTR; reference: just released movie Interstellar, a respected relativist, Thorne, made discoveries while consulting for the movie).

Quantum Physics makes causation a worse consideration than ever. As it stands, the Quantum is Non-Local. No need to get into Spin and Bell, to figure that one out: the analysis in Quantum Hilbert space uses time only as a one parameter transformation group, it’s intrinsically Non-Local (hence the famed “Collapse of the Wave Packet).

If a physicist changes a spin axis on Earth, does it do something to the second member of the entangled photon pair he sent to Beta Centauri? Instantaneously? Really? No one knows for sure (and I don’t believe the “instantaneous” part), but the present Quantum formalism (sort of) says it does.

Paradoxically, all of this debate about cause and effect has become very practical, in the most fundamental domain possible, Quantum Physics. As real physics moves away from the multiverse derangement syndrome, it ponders using, as nature and biology, and even evolution do, the Quantum.

Indeed, even biology uses the Quantum to compute, and find best solutions (as was demonstrated in the case of the chlorophyll molecule; much more examples are on the way, including that will demonstrate how a type of Lamarckian evolution works).

However “what causes what” has stood in the way of making Quantum Computers. Real physicists and engineers have been trying to get a handle on causation. One wants to isolate the process of computation, yet get it impacted by complicated inputs, and only these.

Time to spend some money on all this (that means re-direct the economy that way).

Patrice Ayme’

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12 Responses to “Time for Cause & Effect?”

  1. ianmillerblog Says:

    I am not so sure that entropy is about states, although one may measure the entropy of a state. I take the old fashioned view of thermodynamics – entropy = q/T, q the heat, T the temperature. (Yes, it should be in a differential form, but put that aside.) Now, what thermodynamics says is that energy degrades to heat over time, heat being random motion, so in a sense order becomes randomised.

    I also think time is a little different from space. In my opinion, time is absolute because (at least in principle, if not in practice) any observer can always determine the time that has passed from the big bang. At present, the clock is a bit crudely spaced as far as resolution goes, but nevertheless, that does not alter the fact that every observer has a “beginning” reference point.

    • Patrice Ayme Says:

      Time is absolute, because you count it since the Big Bang. That one floored me. Knocked out. Flat on the ground. I never thought of it. True, I am no lover of the Big Bang… I am rather a hater of the Big Bang. Sounds like OK, for a striking idea.

      Except if one invents and considers an infernal machine. Suppose I have a mighty rocket (my vacuum energy propelled motor using thermonuclear fuel as propellant). It goes close to the speed of light and spirals out and around with the home galaxy. Passengers would have aged only a few months since the Big Bang, if one sets it right (as the Big Bang is absurd, I come back with even more absurd counter-examples! ;-))

      Relativistic slowing down of time is real, and will allow Bill Gates and the Brin from Google, and the Z guy who has no face, or their descendants, to be with us for ever… Except of course if they stop all real tech progress in the meantime…
      PA

      • ianmillerblog Says:

        Your rocket goes to the very essence of relativity – it is what the observer sees. Time appears to go slow in that the person ages, but the real question is, what happens when he comes back and sets his clock by the time from the big bang? He gets a different time from the person who did not travel, yet both make the same observation? That gives me a problem, because the history of the observer should not influence an observation. (Other than competence in carrying it out.) Yes, he has not aged (according to relativity – we have yet to actually demonstrate this in actuality) but where he stops he must be able to determine the time after the big bang there, and it has to be the same as someone who has not travelled.

        The other alternative is the effects of the electromagnetic field are a function of velocity. It is not that the person has not “aged” in the sense that time has not passed, but rather the person’s chemistry has slowed down, and if you travel at light speed it stops entirely because electrons in orbitals cannot exceed the motion of the vehicle when their vector is in the same direction.

        Actually, I hadn’t thought of this before, so maybe I shall have to think further, but this seems to me to have the makings of an Ehrenfest-type paradox

        • gmax Says:

          This stuff, time dilation, is completely proven, demonstrated,
          GPS, whatever…

          • ianmillerblog Says:

            The GPS is thoroughly proven, but how many of the equations have only time as a variable? There is no doubt the equations give the correct observations, but that does not mean we are properly interpreting what the equations mean.

        • Patrice Ayme Says:

          New Year is upon us, remarks will be brief. Actually I am going to re-open another comment. You point at something really fascinating, indeed. History ought not to depend upon the observer. Yet, it does. Poincare’ had found that for Relativity. Two events succeeding each other in one frame, the other way in the other…
          But indeed the BB ought to have an absolute character…

          BTW, time dilation was thoroughly proven by MUONS, long ago.

          Fast travel slows down light, hence all electromagnetic processes.

          • ianmillerblog Says:

            Dear Patrice,

            Yes, two well-separated observers can see sequences of events in different orders, but I see that as a consequence of the constancy of light speed.

            Yes, fast travelling muons have a longer lifetime, but that does not mean time is dilated; it could also mean the decay process is slowed.

            Let me put it this way. An astronaut, after engraving his time after BB in granite sets off at light speed, circulates Andromeda, and comes back. There he meets another physicist, and they decide to measure the time after the BB. There is one experiment, that gives a reading on one meter. Are you telling me that the Astronaut will see the meter read one and a bit Gy less than the other physicist?

            • Patrice Ayme Says:

              Dear Ian: What you are pointing out is that the Big Bang gives an absolute time, an absolute clock. Well, it gives other absolute things, supposedly.

              Henri Poincare’ (the one of the constancy of the speed of light and relativity of chronology) said that, when something is always true, it’s a law of nature. “Decay process slowed” exactly as expected by the slowing of light clocks means time is slowed, because if all definitions of time are slowed just the same, well, time is slowed down.

              The question you have is answered by the movie “Interstellar”. Although there it’s 51 years, not a Gigayear. There is zero doubt in my mind that, by going back and forth at nearly the speed of light, astronauts will be able to reappear in the future of their Earth bound family. (Interstellar uses a rotating Black Hole, but that’s just the same, conceptually speaking.)

              Happy new year

            • ianmillerblog Says:

              Dear Patrice,

              My thoughts on this are getting too fragmented, so I might do a post on my own blog, putting it all together in sequence. The argument is essentially, is time slowing down, or are rate “constants” really functions of velocity?

              Happy New year to you too, and anyone else reading this far.

            • Patrice Ayme Says:

              Happy New Year to you too. Keep me informed on the post.

              Basically “time”, as use in Relativity, is an abstraction for physical processes. The ideas come from Lorentz and Poincare’, NOT Einstein (who borrowed and confirmed). Local time.

              In Quantum, time is magical, primary, unattached. Fundamental, not space.

  2. gmax Says:

    Fascinating. It reminds me of Socrates and the Delphi Oracle you spoke about: a lot of our knowledge consists in discovering we are crass ignorant. Or we were crass ignorant.

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