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Pentcho Valev

Posts: 4,616
Registered: 12/13/04
Posted: Feb 10, 2013 1:50 AM
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QUANTUM GRAVITY IN PERSPECTIVE, LMU Munich, 31st May - 1st June 2013: "The search for a theory which would unite the insights of general relativity with those of quantum theory, a theory of quantum gravity, has now lasted the better part of a century. Although a number of promising candidate theories have emerged (string theory and loop quantum gravity being the most prominent), a large array of conceptual, formal and methodological issues are still unresolved. The increasingly fractured nature of the field ? with long standing and well publicised disagreements over the premisses, goals and criteria for evaluation relevant to a 'theory of quantum gravity' ? might be seen as one significant factor impeding progress. (...) INVITED SPEAKERS: Nazim Bouatta (Cambridge), Richard Dawid (Vienna), Johanna Erdmenger (Max Planck Munich), Sabine Hossenfelder (NORDITA), Claus Kiefer (Cologne), Brian Pitts (Cambridge), Dean Rickles (Sydney), Nicholas Teh (Cambridge), Chris Wuthrich (UCSD)"

Einsteinians are going to extract career and money from this "search for a theory which would unite the insights of general relativity with those of quantum theory" for yet another century although they all know that "the root of all the evil" is the absurd special relativistic time, a direct consequence of Einstein's 1905 false light postulate:

Frank Wilczek: "Einstein's special theory of relativity calls for radical renovation of common-sense ideas about time. Different observers, moving at constant velocity relative to one another, require different notions of time, since their clocks run differently. Yet each such observer can use his "time" to describe what he sees, and every description will give valid results, using the same laws of physics. In short: According to special relativity, there are many quite different but equally valid ways of assigning times to events. Einstein himself understood the importance of breaking free from the idea that there is an objective, universal "now." Yet, paradoxically, today's standard formulation of quantum mechanics makes heavy use of that discredited "now." Playing with paradoxes is part of a theoretical physicist's vocation, as well as high-class recreation. Let's play with this one. (...) As we've seen, if a and b are space-like separated, then either can come before the other, according to different moving observers. So it is natural to ask: If a third event, c, is space-like separated with respect to both a and b, can all possible time-orderings, or "chronologies," of a, b, c be achieved? The answer, perhaps surprisingly, is No. We can see why in Figures 5 and 6. Right-moving observers, who use up-sloping lines of constant time, similar to the lines of constant t2 in Figure 2, will see b come before both a and c (Figure 5). But c may come either after or before a, depending on how steep the slope is. Similarly, according to left-moving observers (Figure 6), a will always come before b and c, but the order of b and c varies. The bottom line: c never comes first, but other than that all time-orderings are possible. These exercises in special relativity are entertaining in themselves, but there are also serious issues in play. They arise when we combine special relativity with quantum mechanics."

Joao Magueijo, Faster Than the Speed of Light, p. 250: "Lee [Smolin] and I discussed these paradoxes at great length for many months, starting in January 2001. We would meet in cafés in South Kensington or Holland Park to mull over the problem. THE ROOT OF ALL THE EVIL WAS CLEARLY SPECIAL RELATIVITY. All these paradoxes resulted from well known effects such as length contraction, time dilation, or E=mc^2, all basic predictions of special relativity. And all denied the possibility of establishing a well-defined border, common to all observers, capable of containing new quantum gravitational effects."

"Many physicists argue that time is an illusion. Lee Smolin begs to differ. (...) Smolin wishes to hold on to the reality of time. But to do so, he must overcome a major hurdle: General and special relativity seem to imply the opposite. In the classical Newtonian view, physics operated according to the ticking of an invisible universal clock. But Einstein threw out that master clock when, in his theory of special relativity, he argued that no two events are truly simultaneous unless they are causally related. If simultaneity - the notion of "now" - is relative, the universal clock must be a fiction, and time itself a proxy for the movement and change of objects in the universe. Time is literally written out of the equation. Although he has spent much of his career exploring the facets of a "timeless" universe, Smolin has become convinced that this is "deeply wrong," he says. He now believes that time is more than just a useful approximation, that it is as real as our guts tell us it is - more real, in fact, than space itself. The notion of a "real and global time" is the starting hypothesis for Smolin's new work, which he will undertake this year with two graduate students supported by a $47,500 grant from FQXi."

Pentcho Valev

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