The Physics and Philosophy of Time – with Carlo Rovelli

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From Boltzmann to quantum theory, from Einstein to loop quantum gravity, our understanding of time has been undergoing radical transformations. Carlo Rovelli brings together physics, philosophy and art to unravel the mystery of time.
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Time is a mystery that does not cease to puzzle us. Philosophers, artists and poets have long explored its meaning while scientists have found that its structure is different from the simple intuition we have of it. Time flows at a different speed in different places, the past and the future differ far less than we might think, and the very notion of the present evaporates in the vast universe.

Carlo Rovelli is a theoretical physicist who has made significant contributions to the physics of space and time. He has worked in Italy and the US, and is currently directing the quantum gravity research group of the Centre de physique théorique in Marseille, France. His books ‘Seven Brief Lessons on Physics’ and ‘Reality Is Not What It Seems’ are international bestsellers translated into forty-one languages.

This talk and Q&A was filmed in the Ri on 30 April 2018.

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Rayne Ma says:

Be exist and not exist.

TK says:

Meteorology – is a study of future prediction.

Tech Tacho says:

We measure time using earth moving through space, which is practical, but never made sense to me on a contextual level. The earth revolving around the sun and on its axis does not affect its age or the ‘time’ until its demise or our aging process and demise. No real link to change or entropy. The sun’s age and how much hydrogen and helium is left in it or the earth’s geological process or our own cellular aging process is more fitting to measuring time for us. But of course that would take a lot more precision and understanding to create a standard of time we can use. But I agree, Time is impossible to lock down due to its point of reference is different for everyone and everything through out the universe and beyond. 13.7 billion years for us can mean 6 days or 6 minutes or instantaneous for some other being or some other object. All it takes is distance in space-time which widens the interval considerably, and beyond this universe it can reach infinite intervals. We don’t like infinity, because it breaks down our understanding of nature, and our ability to measure it, but that’s just our own limitations.

Maurizio Marcon says:

It was very painful to listen to Dr Rovelli. I saw the video many times and try to understand but he was extremely confusing (and confused?) and never got to the point.
Please improve your communication skill and come back again

peterboy sonicat says:

Only three (3) absolutes in the universe. Death, taxes and the irreversal of time. TIME! is the only irreversal property of existence IMHO. So, you must get it right the first time. All frequencies occur in time and visa versa.

Günter Sostaric says:

Already Hume (brit. Philosopher of 18th century) has explained that time can only exist in our heads

Luis Luque says:

Boltzmann equation [ S=k.ln(W)] doesn't mean a system is disordered but the probability how a system can be disordered

Eugene Bird says:

At 22 minutes, Rovelli makes a terrible Mistake – nature knows past from future because electroweak hypercharge knows left spin vs right spin particles. If time went backward, right spin becomes left spin. Also Kaons violate T symmetry, I understand.

Hyborian Age says:

He conflates "now" with the light image. There really is an objective now in the next galaxy. It is irrelevant that we see the light coming from it years later. We are aware that the light we are seeing is from their past and we know it is not their "now."

Deepforce3000 says:

we do not know the nature of reality

Kevin Van Vooren says:

I'm so tired of racist innuendo in these lectures

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