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Physics, Astronomy & Cosmology / Re: Was the Big Bang the beginning of the universe?

« on: 15/10/2019 14:01:19 »

Relevant to this thread?

"Truth is ever to be found in simplicity, and not in the multiplicity and confusion of things".
-- Sir Isaac Newton

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Physics, Astronomy & Cosmology / Re: What is the cosmic microwave background?

« on: 08/10/2019 19:30:10 »

It is easy to understand that the sun has already gone down 8 minutes before one sees it set but I can understand the difficulty in visualising the formation of the CMB.

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Physics, Astronomy & Cosmology / Re: Was the Big Bang the beginning of the universe?

« on: 15/09/2019 18:40:29 »

Sidney Morgenbesser, his professor at Columbia, said to Jim Holt "even if there was nothing you still would not be satisfied".

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Physics, Astronomy & Cosmology / Re: Was the Big Bang the beginning of the universe?

« on: 12/09/2019 09:12:31 »

I recollect the words of John Wheeler, he concluded:

Can we ever expect to understand existence?
Clues we have and work to do, to make headway on that issue.

Surely someday, we will grasp the central idea of it all as so simple, so beautiful, so compelling that we will all say to each other, “Oh, how could it have been otherwise! How could we all have been so blind so long”!

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Physics, Astronomy & Cosmology / Re: Was the Big Bang the beginning of the universe?

« on: 17/08/2019 08:43:39 »

Sean Carroll believes the universe is infinite in both directions i.e. it never had a beginning, it was always there and it will never end.

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Physics, Astronomy & Cosmology / Re: What are the implications of a change in the Hubble constant?

« on: 10/08/2019 10:39:38 »

Is that all?

The news item I read was headlined -- New measurements could upend the standard theory of the cosmos that has reigned since the discovery of dark energy 21 years ago.

But it did not say how.

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Physics, Astronomy & Cosmology / What are the implications of a change in the Hubble constant?

« on: 09/08/2019 19:26:28 »

I am asking this after Wendy Freedman and Adam Riess recently made their case for different expansion rates of the universe.

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Physics, Astronomy & Cosmology / Re: How well do laymen understand Bell's theorem?

« on: 07/08/2019 16:55:59 »

The YouTube "fast talker" could do with slowing down.

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Physics, Astronomy & Cosmology / Re: What is the carbon footprint of Apollo 11?

« on: 11/07/2019 18:54:26 »

But does not the production of the hydrogen and hydrazine add to the carbon footprint?

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That CAN'T be true! / Re: LIGO represents an mirror displacement of what?

« on: 24/04/2019 21:20:08 »

Modern technology can accurately measure time to 3.5 parts in quintillion (10¹⁸): https://www.newscientist.com/article/2149568-the-most-precise-atomic-clock-ever-made-is-a-cube-of-quantum-gas/

Why you think we can only measure time to 1 part in 1,000 is beyond me...

You are mistaken the time that is produced by a clock with the measurement of a time interval. Example, to measure the time of a person running the 100 meter dash; the measurement uncertainty to measure the time interval to complete the race is dependent on the mechanism that determines when the person starts and stops. The uncertainty of the actual time (3.5 parts in quintillion) is trivial compared to the start-stop uncertainty.

I think you should let this guy have the last word.

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Physics, Astronomy & Cosmology / Re: Could the universe be a simulation?

« on: 15/04/2019 20:21:25 »

Simulation of what?

So it's basically whether in the beginning god hit the enter key and then there was light
or if he hit the delete key and then there was light.

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Physics, Astronomy & Cosmology / Could the universe be a simulation?

« on: 15/04/2019 18:43:34 »

Recent expressed views ranged from a reluctant yes from Zohreh Davoudi to no from Lisa Randall and maybe's from Max Tegmark and David Chalmers.

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Physics, Astronomy & Cosmology / Re: Is this simplification of Quantum Erasing correct?

« on: 15/04/2019 12:44:14 »

I find it unsettling that even after 50 years since the single electron double-slit diffraction was first demonstrated by Giulio Pozzi that no plausible explanation has been given.

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Physics, Astronomy & Cosmology / Re: Could String Theory become useful (anytime soon)?

« on: 05/04/2019 09:36:07 »

I never understood why string theory took off and did Stephen Hawking agree with me?

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New Theories / Re: Consolidated empirical evidences disprove black hole (with new evidences)

« on: 30/03/2019 09:48:25 »

Re jose s. aldea Physicist
Tempted to ask "is this cosmobabble"?

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Physics, Astronomy & Cosmology / When will quantum supremacy be achieved?

« on: 16/03/2019 14:42:52 »

The date seems to have slipped through 2017 and 2018.
Could 2019 be a possibility?

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Physics, Astronomy & Cosmology / Re: Do you think we are alone in the Milky Way?

« on: 02/03/2019 16:36:44 »

Susan Schneider, an associate professor of cognitive science at the University of Connecticut says “I’m actually concerned that technological civilizations may not last long, but if they do, there are a lot of reasons to believe they’ll be post-biological artificial intelligence".

Schneider considers that they are already out there and have been for eons.
The age of our solar system is about 4.5 billion years. Earth-like planets have been discovered around stars which are 10.5 billion years old so they will be 6 billion years ahead of Earth.

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New Theories / Could our universe have an antimatter partner?

« on: 10/01/2019 08:02:24 »

Neil Turok and his colleagues at the Perimeter Institute for Theoretical Physics are suggesting that an anti-universe before the Big Bang when time ran backwards and was dominated by antimatter instead of matter.

They say it naturally explains the existence of dark matter.

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Physics, Astronomy & Cosmology / Why did Einstein think we are we all wrong?

« on: 31/12/2018 17:21:59 »

Towards the end of his life, Einstein said
"All these years of conscious brooding have brought me no nearer to the question - what are light quanta? Every Tom, Dick and Harry thinks he knows it but he is mistaken.''

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Physics, Astronomy & Cosmology / Re: Why do we have two high tides a day?

« on: 23/12/2018 23:17:09 »

Is this the answer?