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Narendra Nath: on 12/25/08 at 11:42am UTC, wrote Just a couple of sentences more, specially on the last three lines of your...

Narendra Nath: on 12/23/08 at 16:27pm UTC, wrote Thanks for the response that met my queries well. Best wishes for your...

C. K. Raju: on 12/21/08 at 4:04am UTC, wrote Dear Dr Stoica, Thanks for your comments and for your interest in my...

C. K. Raju: on 12/21/08 at 2:35am UTC, wrote Dear Mr Nath, Apologies for this delayed response, as I was otherwise...

Cristi Stoica: on 12/16/08 at 19:50pm UTC, wrote Dear Dr. Raju, I find very interesting your FDEs applications to the...

Narendra Nath: on 12/15/08 at 10:45am UTC, wrote i read the full text of your paper & found it refreshing in many ways. Yes,...

Anonymous: on 12/8/08 at 9:12am UTC, wrote Dear Mr Nath, Sorry for this delayed response. I didn't respond to paras...

Narendra: on 12/4/08 at 8:19am UTC, wrote Dera Raju, i was frank enough to tell you that i was commenting on the...


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August 16, 2018

CATEGORY: The Nature of Time Essay Contest (2008) [back]
TOPIC: Time and Life: Testing a Tilt in the Arrow of Time by C. K. Raju [refresh]
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C. K. Raju wrote on Dec. 1, 2008 @ 10:54 GMT
Essay Abstract

Do physical influences occasionally travel from future to past? How should this be tested experimentally? (We restrict ourselves to time-travel of the second kind.) Partridge-type experiments, based on absorber theory, lack a clear interpretation since the Wheeler-Feynman theory is circular, and even alternative absorber theories involve complex hypotheses. (Mere verbal reasoning about time is paradox-prone since it simultaneously uses the notion of time already in the tense-structure of language.) Hence, the desirable theoretical starting point is a mathematical model obtained by dropping just the one hypothesis of ``causality''. Functional differential equations (FDEs) are a necessary though neglected consequence of classical electrodynamics and relativity (without any additional hypotheses). Dropping the hypothesis of ``causality'', or admitting a ``tilt'', makes these FDEs of mixed-type---this is the required mathematical model. (These equations imply phenomena such as quantum interference regarded as unique to quantum mechanics, though we do not discuss that here.) Retarded FDEs cleanly resolve the classical recurrence and reversibility paradoxes of thermodynamics, and explain (fine-grained) entropy increase. Mixed-type FDEs imply also occasional spontaneous decrease of entropy. It is mathematically impossible to replicate this mechanically---thus avoiding perpetual motion machines. On mundane observation, living organisms do exhibit occasional non-mechanical behaviour. The value of experimentation, itself, rests on this belief. We conclude that a tilt is consistent with empirical observations, and provides a non-mechanistic physics better suited to model life. This conclusion may be further tested by applying this model to biological macromolecules.

Author Bio

C. K. Raju holds degrees in physics and mathematics, a PhD from the Indian Statistical Institute, and helped build Param, India’s first parallel supercomputer. He has several papers and two books on time. In "Time: Towards a Consistent Theory" (Kluwer, 1994) he proposed a new physics based on a “tilt” in the arrow of time, and pointed out the implications for quantum mechanics. He explored time at the interface of science, religion, and ethics (The Eleven Pictures of Time, Sage, 2003), and was on the editorial board of the Journal of Indian Council of Philosophical Research.

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Dr. E (The Real McCoy) wrote on Dec. 1, 2008 @ 17:45 GMT
Thanks for the paper!

You write, "(Mere verbal reasoning about time is paradox-prone since it simultaneously uses the notion of time already in the tense-structure of language.)"

Well, using math does not necessarily allow us to escape the tautological, circular definitions of time.

You write, "Briefly, Maxwell’s equations admit two types of solutions: retarded and advanced,...

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C. K. Raju wrote on Dec. 2, 2008 @ 01:05 GMT
Thanks for the post Dr E. Here are some immediate clarifications.

First, I do not subscribe to the idea of mathematics as truth or even tautology. My fallibilist philosophy of mathematics is articulated in my book "Cultural Foundations of Mathematics" (Pearson, 2007). That book also examines the significance for mathematics of the time-logic relation that I use to connect a "tilt" to quantum interference via quantum logic.

I agree with Poincare that geometry is convenient, not true.

Against this background, the point of advocating a mathematical model is that it forces us to lay on the table our metaphysical assumptions about time so that they can be examined and rejected if necessary.

Thus, Newton's view of time was metaphysical. ("Absolute, true and mathematical time...flows...without relation to anything external"; note the series of adjectives "absolute", "true", "mathematical" intended to emphasize that Newton's time is metaphysical, and has no relation to anything external). Newton thought this metaphysical belief about time was essential to justify his use of the calculus ("fluxions") needed for the Newtonian view of physics as ODEs.

However, electrodynamics threw a spanner in this Newtonian scheme of things, forcing a more physical view of time and its measurement. The theory of relativity flows from Poincare's postulate that the speed of light must be constant (and that physically defines "equal intervals of time"). [For details please see the chapters in the part on "The Measurement of Time", in my book "Time: Towards a Consistent Theory", Kluwer, 1994.]

Unfortunately, in almost a century, it has not been clearly and widely understood that FDEs are a natural and necessary consequence of relativity.

As Benjamin Whorf suggested long ago, this difficulty in understanding relativity may be due to the metaphysical assumptions about time in English. He argued that the Hopi language has a different metaphysics of time, therefore the Hopi would not have had any such intuitive difficulties with relativity.

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Narendra Nath wrote on Dec. 3, 2008 @ 13:50 GMT
Dear Raju,

i enjoyed the abstract of the essay, questioning the concept of 'causality'. it is nice to question the 'established' concepts if one wants to do some thing innovative. You also talk of physical interference by future into past! You are modeling mathematically but one does require some observed physical reality in Physics before proceeding mathematically. Purely mathematical concepts are good in pure Maths. but we can extend the same in Physics on some sound logical/observed consideration.

i have been speculating about the missing order in considering physical processes using probability. If some individual events have slight degree of correlation, the assumption of complete randomness falls! Order contains disorder but not the other way around. How to consider such interference in processes we assume to have completely random individual events. Can Chi-square test even the slightest of lack of randomicity?

Nature shows highly intelligent logic in its evolution of the Universe. How can order be completely missing when a physical process is described purely on the basis of 100% randomcity of individual events? We ahve gone thus far in Physics without such considerations, as we seem to get exptal data to conform to the statistical averaging. However, individual events that we are unable to observe, may have some directed correlation with 'order' that remain illusive because of our limitations in measurements.

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C. K. Raju wrote on Dec. 4, 2008 @ 04:31 GMT
Dear Mr Nath,

Thanks for your post. You say you have read the abstract, but may I draw your attention to the sub-title: "Testing a tilt in the arrow of time". The operative word is "TESTING". The paper is about how to experimentally test whether the cosmos is fully causal or only partly so.

In case you missed the title, this is clarified in the second line of the abstract: "how should this be tested experimentally?"

The point of the paper is to experimentally test the dogma of perfect causality. I am not ready to take anyone's word about the nature of reality. So, where is the experimental support for this dogma? For such experimental support, we should be able to say (1) here is this theory A which is perfectly causal and (2) here is theory B which is exactly like theory A except that it allows some "violations" of causality, and (3) experiment supports theory A over B. But you criticise me for even thinking about such a theory B! That is why I call the belief in perfect causality a dogma. Don't you agree that the nature of reality should be decided by experiment? And for an experiment to be meaningful don't we need competing theories?

The mathematical model I talk of is derived from just Maxwell's equations and the Heaviside-Lorentz force law. NO FURTHER ASSUMPTIONS---not even the assumption of perfect causality!

Just any experiment and just any theory which rejects causality won't do. Partridge carried out an experiment based on the Wheeler-Feynman theory. The experiment could neither reject nor confirm the theory. Moreover, the Wheeler-Feynman theory is internally inconsistent.

So what we need is to derive empirical consequences starting from a good theory which drops from standard physics just the one assumption of causality. I thought I had stated this point clearly in the abstract.

That leads to the mathematical model above. You are quite right that pure mathematics may not lead to a good physical theory. But that remark is completely irrelevant to my paper.

More to the point, bad mathematics does not lead to good physics either, and, in the last century, physicists treated the classical electrodynamic n-body problem in a mathematically incorrect way.

Finally, my point is that if we do things the corect way, then (non-mechanical) life is an expected empirical consequence of such a physics without perfect "causality". It would be pretty sad if that were not part of reality!

Therefore, may I suggest that you read the paper before commenting on it?

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Narendra wrote on Dec. 4, 2008 @ 08:19 GMT
Dera Raju,

i was frank enough to tell you that i was commenting on the essay just after seeing only the abstract. This problem arose as i had the impression that the last date for postings was dec., 01 butv it seems it got extended! i apologize for half cooked study before putting in my equally unjustified comments.

However, i am not fortunate to see your ideas on paras 2 and 3 of my post.It will also be of help if you may consider response on my essay too in this competition, so that we may establish better understandings about our respective contributions. No more comment now until i see the full text of the essay!

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Anonymous wrote on Dec. 8, 2008 @ 09:12 GMT
Dear Mr Nath,

Sorry for this delayed response. I didn't respond to paras 2 and 3 of your post since the points that you are making in those paras are not clear, at least not to me (though I have taught probability and statistics and have long used the notion of order/entropy, as in my paper here).

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Narendra Nath wrote on Dec. 15, 2008 @ 10:45 GMT
i read the full text of your paper & found it refreshing in many ways. Yes, i seeem to understand better what you term as a tilt in the time arrow. You propose an Expet. that should be able to detect excited system emitted radiation to be detected such that one separates out the prompt and retarded components. The former is expected to be weak. You suggest that biological macromolecules, like the human proteins are ideal for such a study.

You do talk about there is something about living organisms connected with creativeness that may well result in isolating such a behavior. Do you mean that the process then does become not 100% random in nature. That is it is not a pure chance phenomenon! That creativity is tied to an element of order in the observed effect.

The points i happen raise in para 2 &b 3 of my previous post were concerned with what little i know of statistics. There is a Chi-square test that you perform on a set of a large no. of observations of any process. If there is any regular event(s) mixed with purely random events that gets identified from the deviation of Chi-square value for the degrees of freedom to lie witin the probability curve range of 5-95% range out of 100.

The third paragraph desired your opinion on the aspect of evolution of the Universe that appears to follow a logical design. Then , one may say that the reality lies in order hidden within the randomicity of the events observed for any physical process/phenomenon being studied at any given time.

i hope i have made some tangible queries for your expert response!

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Cristi Stoica wrote on Dec. 16, 2008 @ 19:50 GMT
Dear Dr. Raju,

I find very interesting your FDEs applications to the electrodynamics n-body problem. I have a question. If we consider only the sources (charged particles), in order to describe the evolution, we need to use the FDEs. This leads, for the retarded potentials case, to a confluence of the phase space trajectories, and in the case of advanced potentials, to a branching. My question is: If we reintroduce the electromagnetic fields, together with the sources, don’t we regain the “Newtonian paradigm”? If this is so, then in the retarded case the systems will be identical after t>1 (fig. 2) only in the sources, but not in the electromagnetic fields. In the advanced case, the causality is preserved, being hidden in the fields, which disturb the charged particles to evolve differently in the three cases, after t>0 (fig. 3). The same happens for the mixed FDEs. In all three cases, it seems that if we account for the fields, we obtain the same two-ways deterministic view as in the case of the PDEs.

I think that you are right to say that the electromagnetic arrow of time explains, at least partially, the thermodynamic arrow.

I like the idea of the tilt in the arrow of time. Perhaps it can be related with my essay, in which I apply an apparently countercausal reasoning in Quantum Mechanics, as well as in the problem of free will.

Best wishes,

Cristi Stoica

Flowing with a Frozen River

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C. K. Raju wrote on Dec. 21, 2008 @ 02:35 GMT
Dear Mr Nath,

Apologies for this delayed response, as I was otherwise preoccupied.

You are quite right that I am saying that creativity is not a 100% random process, and that it relates to creation of order.

Indeed, this is the key point of my model that it makes order creation possible, without introducing any new physical hypothesis. My model permits processes that are (a) "spontaneous" in the sense of being unpredictable from the past, and also (b) create order.

This is exactly why my model is able provide such a natural account of the observed existence of life, and complex ordered systems. Even the origin of life now appears as something natural rather than mysterious, as it would be under "randomness".

Mathematically speaking, by "randomness" or chance, I understand a process modeled by stochastic differential equations (SDEs) which is unpredictable from the past, but nevertheless remains probabilistically predictable. Physically, such random processes lead to decreased order or increased entropy (on stock thermodynamics). Thus my model, using mixed-type FDEs, provides an account of spontaneity which is both mathematically and physically distinct from "randomness" or "chance".

As regards your question about possible design in the cosmos which is hidden under apparent randomness, it seems to me that this question perhaps goes beyond physics. You are doubtless aware of the answer in the RgVeda that only he in the highest heaven knows, or perhaps even he knows not!

Possibly the cosmic design is partly our own. And we would better understand things if we were able to model our apparent mundane ability to design a tiny bit of the future cosmos.

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C. K. Raju wrote on Dec. 21, 2008 @ 04:04 GMT
Dear Dr Stoica,

Thanks for your comments and for your interest in my paper, and apologies for this delayed response.

First of all may I clarify that, in my book "Time: Towards a Consistent Theory" (Kluwer 1994) I proposed FDEs as a generalised model of physical time evolution, and not merely for electrodynamics. (This is why I have remarked that I regard General Relativity as an...

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Narendra Nath wrote on Dec. 23, 2008 @ 16:27 GMT
Thanks for the response that met my queries well. Best wishes for your continuing success professionally

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Narendra Nath wrote on Dec. 25, 2008 @ 11:42 GMT
Just a couple of sentences more, specially on the last three lines of your dec., 21 post to me. I really like the way you put. The evolutionary aspect is logical because we think so or else we need to build a bit of 'future' universe ourselves to project the matter further! i wish you all success,as you have the time to accomplish such apparently difficult propositions being carried to some conclusive end.

If you have some comments on my essay, may i see it on my essay post, as i expect U to come out with something worthwhile.

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