On Tuesday, June 25, 2019 at 1:56:40 PM UTC-5, Eva wrote: > > Lawrence Crowell > > I love his ideas, they deliver answers to many fundamental questions - why > there is something rather than nothing, why Mathematics is so much > effective in Physics, what is consciousness etc. > > Let me quote a passage about time from his article: > > [quote] > > "Similarly, space and time are fundamentally different, and not just > mathematically, as real and imaginary quantities. The root cause is that > time is continuous and space is not. Time’s continuity has many > consequences. It means that time is irreversible. To reverse time, we would > have to create a discontinuity, a zero-point, and it would no longer be > continuous. Time also is not an observable in quantum mechanics, because > observables must be discrete. And it is always treated as the independent > variable; we write dx / dt, not dt / dx. > > The absolute continuity of time is important in the explanation of the > paradox of Zeno in which Achilles never catches the tortoise, however fast > he runs, if he gives it a start, and the same is true of other paradoxes of > a similar nature. Various authors have seen that the problem lies in the > assumption that one can divide time into observational units like space. > Whitrow, for example,3 writes that: ‘One can, therefore, conclude that the > idea of the infinite divisibility of time must be rejected, or … one must > recognize that it is … a logical fiction.’ Motion is ‘impossible if time > (and, correlatively, space) is divisible ad infinitum’. And Coveney and > Highfield4 propose that: ‘Either one can seek to deny the notion of > ‘becoming’, in which case time assumes essentially space-like properties; > or one must reject the assumption that time, like space, is infinitely > divisible into ever smaller portions.’ Perhaps because of the many > historical efforts to link space and time in a more than mathematical > sense, such authors seem to be reluctant to draw the logical conclusion > that the paradox, like many others, really is a result of making things > that are fundamentally unlike have the same properties. Space is > ‘infinitely divisible into ever smaller portions’; time is not divisible at > all. What we call ‘divisions of time’ are not observed through time at all. > > Again, all normal physical equations are time-reversible, but time is not. > We know this from the second law of thermodynamics." [/quote] > > > > https://www.google.com/amp/s/bsahely.com/2018/06/17/are-there-alternatives-to-our-present-theories-of-physical-reality-by-peter-rowlands/amp/
I looked at the paper Philip referenced. He is big on quaternions. He was interested in a quaternion approach to QCD. https://arxiv.org/ftp/arxiv/papers/0912/0912.3433.pdf <https://www.google.com/url?q=https%3A%2F%2Farxiv.org%2Fftp%2Farxiv%2Fpapers%2F0912%2F0912.3433.pdf&sa=D&sntz=1&usg=AFQjCNFlZIgChk2tEz3fImk3VGSM-ZvdOA> There is a quaternion form of time reversal. I am not sure about his claim that space is discrete and time not. Spatial and temporal coordinates are interchangeable with Lorentz transformations. A transformation between something that is continuous and another that is discrete would require a sort of incredible "fine tuning." The Fermi and Integral spacecrafts also found that a wide range of spectra arrived from burstars billions of light years away arrived at the same time. If space were discrete, say made of Planck scale cells then a photon with momentum p = ħk would have a propagator G(k, 0) ~ 1/[4π(k^2 - ℓ^{-2})] for ℓ the scale of the discreteness of space. This would mean photons with different wavelengths would have different phase velocities and there was be some dispersion. That is not experimentally found. He is appealing to entropic time to argue there is not reversal of time with respect to quantum mechanics. The problem is this is two domains of physics. Quantum information and entropy is constant for transformations and evolution of pure states. The relationship between quantum time and entropic time is not entirely known. LC -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/1796f341-a52f-4bef-996b-6718a9ddf0f9%40googlegroups.com.
