The Destiny of the Universe

Here is a nice and clear explanation by Sandu Popescu of what is going on here :

http://physics.aps.org/articles/v2/32

Causality is not violated because post-selection happens after the middle weak measurement. And while thinking that the future affecting the past may simplify the analasys, there are highly non-trivial efects in the standard analasys which get hidden, like the existence of super-oscillations: an oscillation of a band-limited function which oscillates faster than its fastest Fourier mode. It all boils down on realizing that weak measurements are not measurements in the normal sense with a link between values and probabilities. In fact weak measurements can even be imaginary and are the effect of averages on the post-selected ensamble.

I disagree with both Sandu Popescu and the author of the paper. Instead of imagining future influences on the past, I think a more fruitful approach is to consider violations of Bell and Tsirelson bounds and clarification of the measurement problem in the mezoscopic domain (i.e. emergence of real measuremet values in strong mensurements from weak measurements featuring complex and values larger than the largest eigenvalue)

I never thought that weak measurements at all implied backwards causality. The value of observable under a weak measurement increases as the pre and post selected states become orthogonal. So the Hardy result of permitting an electron and positron to interfere in a beam splitter is possible as the non-annihilation probability is amplified in this way. The freedom to rotate the pre and post selected states does indeed produce overlaps which are imaginary valued.

This only has something to do with future outcomes maybe in the sense of the Wheeler-Delay Choice experiment. The apparent interference between the pre and post states can be seen I think as a WDC experiment type of thinking.

What Florin indicates here are states which are in between being pure or entangled states and states which are the outcome of measurements. There is this "nether world" in between the two, which may have some relationship to weak measurements.

Cheers LC

WDC, like the 2-slit experiment on which it is based, concerns the path of a single particle. Both 2-slit and delayed choice, then, deal with particle-like properties of the interference pattern.

When we speak of future events meeting present events, we want to stay in the domain of wave-like properties, where the interference patterns (and therefore particle superpositions) are preserved in a 2-point n-dimensional relation. In my model (my "time barrier" paper, eqn 5*) partial order in the moment (the least-time state) is represented by the asymmetry of gravitating bodies -- i.e., the projected area around each point, based on the difference in escape velocities, differs by a slight but nonzero amount. Because escape velocities carry unique values in the gravity field and continuously change with the spacetime field, the field interference patterns maintain continuously changing superposition in a combined field on orthogonal axes.

In general relativity, the state of the spacetime field determines the strength of gravity ("space tells matter how to move"), while matter is at relative rest in the field ("matter tells space how to bend"). In "The relativistic theory of the non-symmetric field" (The Meaning of Relativity, Appendix II, Princeton 1956) Einstein writes, "It does not seem reasonable to me to introduce into a continuum theory points (or lines, etc.) for which the field equations do not hold. Moreover, the introduction of singularities is equivalent to postulating boundary conditions (which are arbitrary from the point of view of the field equations) on 'surfaces' which closely surround the singularities. Without such a postulate the theory is much too vague." What I've done is to project on the Riemann surfaces closely surrounding the singularities (2-point boundary) a time-dependent area which I find does not commute between points, making the time metric n-dimension continuous.

This result suggests that the spacetime field and the gravity field are independent and orthogonal, though combined -- like the electric and magnetic fields.

Tom

*Correcting error in notation: Eqn 5 E_v should be V_e

Tom,

I got here a bit late so I can't write too much. The gravity field has analogues of the electric and magnetic fields. The coordinate and momentum metrics are conjugate in the same way that D and H fields are conjugate. There is likely a departure, for coordinates also do not commute, so there is an extended noncommutative C* system.

More later

Cheers LC

Lawrence,

Let's see if we can find a classical physics example. Suppose we pre-select all attempted conquests of ancient Rome. Then we post-select the cases where the attacker reached Rome but his conquest route was 100% blocked by the Roman armies. Then we ask for the middle measurement: which route did the invading army took? So what we have? We got Hannibal and his Alps crossing. He got from state |A> = attack Rome at time t_1 to state |B> inside the Italian peninsula but with all known paths blocked at time t_3 and = 0 and at time t_2 he was crossing the Alps (weak measurement with amplified values.) But is this proof of backward causation, or of future affecting the present? Not at all. The only valid conclusion is that if you want to transition between near orthogonal states, you need to do things out of the ordinary, or think/act outside the box.

Aharonov's basic equation is: A_w = / and the amplification happens when = almost zero because of the very small denominator.

Let's have another example: . = nearly zero. Let A=a qualifier-type problem. Now pre-select all PhD physics graduate students and post select all Nobel Prize winners. Then one would expect unusually brilliant solutions of the qualifier-type problems for Feynman and others in their graduate student years. And indeed, this is what it happens on average for most of the Nobel prize winners early in their career. But can we conclude this is evidence of the future (winning Nobel prize) affecting the past (a brilliant solution for qualifier-type problems)? No. This is no guarantee of success; it is only a pre-requisite. And here lies the fault of the argument of Aharonov, Davis, and Popescu. Amplified weak measurements are only a pre-requisite of the evolution toward a final orthogonal state, and not a guarantee. There is no destiny at work here.

Let's try this post again with greater then and smaller than signs replaced by paranthesis...

Lawrence,

Let's see if we can find a classical physics example. Suppose we pre-select all attempted conquests of ancient Rome. Then we post-select the cases where the attacker reached Rome but his conquest route was 100% blocked by the Roman armies. Then we ask for the middle measurement: which route did the invading army took? So what we have? We got Hannibal and his Alps crossing. He got from state |A) = attack Rome at time t_1 to state |B) inside the Italian peninsula but with all known paths blocked at time t_3 and (A|B) = 0 and at time t_2 he was crossing the Alps [weak measurement with amplified values.] But is this proof of backward causation, or of future affecting the present? Not at all. The only valid conclusion is that if you want to transition between near orthogonal states, you need to do things out of the ordinary, or think/act outside the box.

Aharonov's basic equation is: A_w = (Future|A|Past)/(Future|Past) and the amplification happens when (Future|Past) = almost zero because of the very small denominator.

Let's have another example: (Future| = (Nobel Prize|. |Past) = |graduate student). (Nobel Prize|graduate student) = nearly zero. Let A=a qualifier-type problem. Now pre-select all PhD physics graduate students and post select all Nobel Prize winners. Then one would expect unusually brilliant solutions of the qualifier-type problems for Feynman and others in their graduate student years. And indeed, this is what it happens on average for most of the Nobel prize winners early in their career. But can we conclude this is evidence of the future [winning Nobel Prize] affecting the past [a brilliant solution for qualifier-type problems]? No. This is no guarantee of success; it is only a pre-requisite. And here lies the fault of the argument of Aharonov, Davis, and Popescu. Amplified weak measurements are only a pre-requisite of the evolution toward a final orthogonal state, and not a guarantee. There is no destiny at work here.

I think there's a bit of conceptual misunderstanding of what one can expect from the back-reaction of future events to present. One is not saying that the present is determined by the future, such that predictions for present states become exact. One is saying that the present is partially ordered, such that assuming least-action, the probability field is restricted to a known or arbitrarily chosen future state. An example of a known future state would be a folded protein (cited in my ICCS 2007 paper linked earlier).

In the Aharonov-Vaidman paper that Florin earlier linked, the authors take a quantum theory approach with a 2-state vector system, and derive classical time symmetry. In my preprint, "on breaking the time barrier" I take a classical approach with a 2-point boundary value, and derive quantum time asymmetry. One should think that these theories are dual, because one would find that the asymmetry my theory predicts for four dimensions is very tiny, and quantum time asymmetry is only apparent in d > 4.

Tom

Aren't D and H fields empirical? My memory is dim on this. What I have in mind, at any rate, is a field conjugation that gives us a direct relation between the classical "corkscrew" path of time and the tensor metric. I know -- that's badly stated; the formalism I imagine, however, should very well show us the restricted domain of future events, even though the range is infinite.

Tom

Hi,

My feeling is that what we take as "the universe" is just our close neighborhood and that the 'cosmic fabric' is as infinite in time as in space.

His nature is being 'energized matter' and no end is available to that (no start, no end).

Accepting this apparently absurd idea seems to be the solution...

Cheers,

Florin,

I agree there is no "destiny" with weak measurements. With the states (f| |p) for future and past states the ratio (f|O|p)/(f|i) for the past and future states nearly orthogonal can be seen as adjusting either of the two states f or p, to preferentially select p or f, or some class of states "close" to them. A perfect selection appears to be where the denominator is zero, but this is a singular case and it appears that this ratio is not physically applicable. It is in this way that this could be seen as a process of manipulating states at one time to select outcomes at another time by their overlaps or measure with an observable or operator.

Cheers LC

Dear Wilton,

Our observable Universe may or may not be infinite. I tend to think it is proportional to a geometrical power of Dirac's Large Number, 10^40 (such as the cosmological constant in 3-D is 10^(-120)~(10^40)^(-3). But if Scale Invariance is true, then our Universe is just a fractal fragment of an infinite Cantor dust. So infinity is the set of self-similar Universes.

Have Fun!

But dear Ray,

The universe is finite, the space is infinite, the time is constant in its locality and moment.

Why do you say that about the infinity.....a set of universes.....that has no sense Ray in a whole point of vue respecting the uniqueness of all thing.

I think it's better to focus on a fractal of a real volume and mass, here the center of our Universe.

The infinity must have its fondamentals also, because we must differenciate the physicality and its intyrinsic laws and the unknown and its eternity if I can say.

Thus when we speak about physics , we accept its laws and equations.

We can see the truth when the confusions appear .....

Friendly

Steve

Future can affect the past ? N0 !

Even past can not effect the future. There is no time in the universe.

UNIVERSE IS NOW.

yours amritAttachment #1: 3_Block_Universe.pdf

Good points, Lawrence -- and exactly the reason I favor a strategy of comnplex analysis on the Riemann sphere to reconcile quantum and classical behavior. The expression 1/0 -- because the Riemann sphere has only the one simple pole at infinity -- is defined to be infinity. This is the division by zero that creates a logical mess in the arithmetic domain.

Using Hawking's analogy of going "north of the North Pole," we find that extending the time trajectory beyond the singularity allows more room for time to be physically real, even in the imaginary domain, without violating quantum unitarity in the real domain.

Tomk

Dear Amrit,

You are quite right, the universe is now! Everything just happens in the very instant of the present. Past is gone and future is an just a possibility.

Meanwhile, life is a trajectory (like a motion), there is a "now", a "before now" and a "after now". So, what happens in the past, do influence both present and future.

Cheers,

I have been saying precisely this for decades now. For example my three books Destiny Matrix, Space-Time and Beyond, Super Cosmos all in print on Amazon et-al. David Kaiser of MIT Physics is writing a book in which I am prominently featured. See also Herbert Gold's 1993 book "Bohemia" Simon & Shuster where the above ideas are documented. I also have two papers on the Cornell archive on this one with Creon Levit NASA AMES also printed in IOP Proceedings of DICE 2008.

Jack Sarfatti, Ph.D. (physics UC, 1969)

http://stardrive.org

Tom,

This is similar to a projective geometry. I would need to sit down with this and see if there is anything to what I see as a connection with the WDC. AS (f| and |i) are rotated to an orthogonal configuration it is uncertain how this sets one state, say |i) given the other.

Cheers LC

Dear Jack,

This does sound a lot like your ideas. Would you like to contribute a more detailed comment or observation to this blog site? Personally, I'm having difficulty imagining the future affecting the past. Do tachyons really travel backwards in time (I realize that the light cone implies this, because tachyons outrace photons) or are they an example of the local present affecting the global present by simultaneously transferring "spooky" action-at-a-distance phenomena?

Have Fun!

Ray Munroe, Ph.D. (HEP-PH physics FSU 1996)

I like your ideas Amrit, youn know it,

but for the past which can affect the future, I do not agree, because all is the result of a polarization of evolution, we were fishs, we were, cells, we were CH4 H2O NH3....WE WERE AND WE SHALL BE ..............I agree thus for the eternity is now .....but we must acept also the physicality and its dynamics.

Best Regards

Steve