I'm reading Paul Davies' book:(adsbygoogle = window.adsbygoogle || []).push({});

About Time:Einstein's Unfinished Revolution

And I have lots of questions....

FTL = t reversal ?

page 177

'photons and a beam-splitter'....

-quote-

...if both photon paths are the same the photons will arrive at the beam-splitter simultaneously and, for reasons of quantum interference, go to the same detector. The optical arrangement in effect provides a racetrack to compare the travel times of the two photons.

Now suppose a barrier is inserted in one of the paths. Because the photon on that route has to tunnel through the barrier, it may not arrive at the meeting point at the same time as its twin, in which case the delicate interference arrangements are upset, and there is a chance that one photon will go to each detector. However, by adjusting the length of the other route (the one that the twin took) to compensate, you can restore the situation and arrange for simultaneous arrival,and infallible cooperation in detector choice, once more.

If the photon is slightly delayed by going through the barrier, then the twin's path will need to be slightly lengthened to compensate. By measuring the extra length, you can work out how long the photon took to tunnel.

When the experiment was actually performed, the results were amazing.

With the barrier inserted, the photon that tunneled arrived first!

In other words, the barrier seemed to speed the photon up.

But the photon was already traveling at the speed of light, so on the face of it the photon that tunneled did so faster than light!

The Berkeley group inferred a boost to the photon's velocity of some 70 percent-i.e., the photon tunneled at over five hundred thousand kilometers per second.

-end quote-

-----------------

After all of that, I'm wondering if this tunnel test actually proves that FTL does NOT equate to 'traveling backwards in time'?

In other words, once the photon was traveling at FTL speeds it should have gone backwards in time from that point, this at the same instant it was 'racing' the other photon.

IF that were the case, the other photon should have WON the race.

But it did not, it was the tunneling photon which won the race.

1) Does this prove that FTL speeds do NOT cause travel backwards in time?

Other , About Time, questions, thoughts, comments, gedankens, and just thinking out loud...

Davies asks the question:

'Do clocks really run slower in the basement?'

(I assume 'his basement' is underground)

Then he goes on to say:

'Not only does time really run faster at higher altitudes, it does so at just the rate that Einstein always said it would'.

But he never really answers his own question, he hints that the answer is 'yes'.....?

I'm still looking for additional data.

2) a) 'Do clocks really run slower in the basement?'

b) How is time affected the deeper you travel underground?

Zero Gravity:

Is it true that the Earth's gravity field is strongest at its surface?

How does or does 'sea level' affect this?

Since stronger gravity fields slow time;

do zero gravity fields have 'faster running time'? (two clock test)

*Is it possible to have a zero gravity field which actually slows time?

I have read that the Earth's core is zero gravity, since you have equal mass on all sides.

3) In this zero gravity field would time actually run slower?

thanx

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# About Time

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