Horizon - Mystery of Dark Energy

Horizon - Mystery of Dark Energy

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Derek Smith

Original Poster:

46,327 posts

254 months

Thursday 31st March 2016
quotequote all
Watched the programme last night and then viewed it again straight afterwards.

I found it fascinating, if more than a little confusing. It was clear from the beginning that no one knows what dark energy and dark matter is, or even if it exists in any real form.

Viewers were left with the feeling that we were waiting for someone to follow in the steps of Newton and Einstein; a genius to revolutionise scientific understanding. There were others who seemed convinced that the big machines will provide the answers.

What was clear at the end was that no scientist has a clue what the stuff is, or even if it is stuff.

Are we there yet?




Eric Mc

122,699 posts

271 months

Thursday 31st March 2016
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I tend to find this subject matter a bit of a turn off. Most of the related TV programmes, are, to me, verging on idle speculation and until someone comes up with some clear explanation or discovery - there is very rarely little new to add.

Toaster

2,940 posts

199 months

Thursday 31st March 2016
quotequote all
Eric Mc said:
I tend to find this subject matter a bit of a turn off. Most of the related TV programmes, are, to me, verging on idle speculation and until someone comes up with some clear explanation or discovery - there is very rarely little new to add.
Of course its a turn off Eric, if it was simple you would be explaining it to all however, real science is hard, it is about uncovering the unknown and possibly the unknowable yet over time discoveries are made. Science is thought provoking, challanging for those in research there is despair and elation.

Not long ago I sat in a lecture regarding column based queries, its well known what the benefits are behind an analytic engine, but this was the Maths behind it, most would find it a turn off some may find it mildly interesting and for a rare few its very exciting.

don4l

10,058 posts

182 months

Thursday 31st March 2016
quotequote all
Dark energy is nothing more than a construct to explain away the fact that the universe appears to be expanding at an increasing rate.

Dark matter is also a construct to explain why galaxies are rotating faster than they should.

The reality, IMHO, is that Einstein was not 100% correct, but scientists do not like to admit that they just don't know.

If we look back into history, every generation had complete confidence in their scientists/religous leaders. Yet, we can see that every previous generation were wrong about almost everything.

How come we are lucky enough to be the first generation where the scientists really have discovered the truth?




Eric Mc

122,699 posts

271 months

Thursday 31st March 2016
quotequote all
Toaster said:
Of course its a turn off Eric, if it was simple you would be explaining it to all however, real science is hard, it is about uncovering the unknown and possibly the unknowable yet over time discoveries are made. Science is thought provoking, challanging for those in research there is despair and elation.

Not long ago I sat in a lecture regarding column based queries, its well known what the benefits are behind an analytic engine, but this was the Maths behind it, most would find it a turn off some may find it mildly interesting and for a rare few its very exciting.
Why do you always get personal?

anonymous-user

60 months

Thursday 31st March 2016
quotequote all
Not seen the program but I find the whole zero energy universe interesting, the positive and negative effect, mainly gravity being the negative force.

I think gravity might have something to-do with dark energy but in it neutral form.

Eric Mc

122,699 posts

271 months

Thursday 31st March 2016
quotequote all
I actually DO find the subject interesting - despite what Toaster intimates. I was referring more to the programme as much as the subject matter

There have been no major breakthroughs over the past few decades so there is little new to say - for the moment.

The recent announcement of the detection of gravity waves MAY lead us in the direction where some explanations as to how the universe behaves on this cosmic scale may be forthcoming - but that is a bit down the line I think.

For the moment, these TV programmes just tend to repeat themselves.

Toaster

2,940 posts

199 months

Thursday 31st March 2016
quotequote all
I wasn't inferring it was what you stated,

Eric Mc said:
I tend to find this subject matter a bit of a turn off.
then a differing statement

Eric Mc said:
I actually DO find the subject interesting - despite what Toaster intimates. I was referring more to the programme as much as the subject matter .
Don't protest to much Eric its not personal

But whatever it is interesting for me particularly as there are no answers but theories awaiting to be proven or otherwise, and that in itself is awesome Science.

Eric Mc

122,699 posts

271 months

Thursday 31st March 2016
quotequote all
Maybe I wasn't specific enough.

I find it a "turn off" as a subject for repetitive TV documentaries.

Finding out about the universe is always interesting. Saying the same things in a TV programme over and over again is not.

Derek Smith

Original Poster:

46,327 posts

254 months

Thursday 31st March 2016
quotequote all
I find it tremendously exciting. 'They' don't know. They are struggling and, thankfully, are not afraid to admit it.

In my day Einstein was a sacred cow. Even his admitted errors were used to show how right he was. Rather oddly, I was told, and believed, that he'd solved it all. Even Hoyle, whom I used to listen to on radio with my brother, father and an uncle or two, with his constant state was proved wrong.

As the years went by I gradually had to admit my faith was doomed. Quantum theory and other discoveries opened up new horizons.

What was good to see was that scientists admitted that they were struggling. That's exciting. There are, we were told, hundreds of theories explaining dark energy/matter. Now that's very exciting. I replayed the programme, although skipped through about 30%, straight after seeing it.

I liked the anticipation in the faces of scientists who were saying they were struggling.

When we do discover what dark thingies are, or at least have a theory that predicts, then who knows what it will open up? Einstein's theories gave us black holes, satnav and other stuff.




Eric Mc

122,699 posts

271 months

Thursday 31st March 2016
quotequote all
Lots of hard to see black holes - that's where the dark matter is.

Where the dark energy comes from - nobody knows.

How close are we to finding out - who knows.

Is "dark energy" a supposition based on a fundamental ignorance of what is really happening - very probably.

ATG

21,157 posts

278 months

Thursday 31st March 2016
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Agree entirely with Eric. You could go back to the 1980s and watch popular science programmes describing most of the same fundamental physics problems that you'll see in contemporary programmes.

I'm surprised anyone was ever under the impression that physicists thought Einstein had "solved everything", nor that it is in any way unusual that physicists are saying "we don't know".

In the grand scheme of things I'm not sure the discovery of dark energy and matter really rank as major problems when compared to the problems of the incompatibility of General Relativity and Quantum Mechanics, and the interpretation of what QM means. This is not to down play the significance of dark energy and matter one iota, but just to point out that in spite of the towering intellectual achievements of GR and QM, physics has always had obvious, gaping holes in it.

Derek Smith

Original Poster:

46,327 posts

254 months

Thursday 31st March 2016
quotequote all
Eric Mc said:
Is "dark energy" a supposition based on a fundamental ignorance of what is really happening - very probably.
It's just a name. They could have called it Kevin. All they are saying is that the universe is not doing what our current theories predict. Or, to put it another way, we are, at the moment, out of our depth. How cool is that?

The knowledge of the existence, if it does exist, of dark matter/energy is fairly recent, the last few years in fact, so it is a bit unreasonable to expect an answer right away.


vanordinaire

3,701 posts

168 months

Thursday 31st March 2016
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I only managed to watch a bit this program before my wife came home last night. Found it really interesting and looking forward to watching it on catchup if I can. Obviously it never came to a nicely rounded conclusion but did it give any hints that we are getting somewhere in our understanding?

Nimby

4,843 posts

156 months

Thursday 31st March 2016
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Pretty amazing that Euclid will photograph more in one day than Hubble will have done in its entire lifetime.

Eric Mc

122,699 posts

271 months

Thursday 31st March 2016
quotequote all
Derek Smith said:
It's just a name. They could have called it Kevin. All they are saying is that the universe is not doing what our current theories predict. Or, to put it another way, we are, at the moment, out of our depth. How cool is that?

The knowledge of the existence, if it does exist, of dark matter/energy is fairly recent, the last few years in fact, so it is a bit unreasonable to expect an answer right away.
I'm not expecting an answer anytime soon at all.

My initial comments were on the nature of a TV programme covering a topic where there is more mystery than knowledge - and the level of knowledge is more or less where it has been since the last time they made a similar programme, and the programme before that.

motco

16,177 posts

252 months

Thursday 31st March 2016
quotequote all
I missed this particular programme, but I admit that I probably would have avoided it anyway. TV documentaries at the moment seem to all too often be inflated half hour programmes that have been stretched to fill an hour long slot. The commentators are not dealing with the real import of the subject but simply glossing over the surface aided by lots of irrelevant visual matter. To understand what sort of presentation I appreciate you need to have seen the Open University programmes that were aired on BBC2 before video tape players were available at home - late seventies and early eighties. To many they would have been dry and boring but they were actually fascinating and very informative in quite short duration slots. For a delivery that cannot be excelled in 'popular' science programmes (not 'shows' as they are now) watch back numbers of 'Tomorrow's World' presented by Raymond Baxter.

Let the flaming begin... getmecoat

Moonhawk

10,730 posts

225 months

Friday 1st April 2016
quotequote all
One thing that occurred to me.

The accelerating expansion of the universe interpretation is based on the fact that distance is measured by red shift and that supernovae at higher red shifts are fainter than we expect them to be - indicating they are further away than expected if the universe was expanding at a steady rate or even slowing down.

But have the models assumed the light has travelled to us in a more or less straight line?

We know that gravity bends light. Could the fact that supernovae are fainter than expected simply be explained by the fact that light from more distant sources will have simply travelled further by following a more wiggly path around the gravitational fields of all the stuff between it and us and therefore lost more light in that journey than it's red shift distance would suggest?

The further away the supernovae - the more stuff there is between us and it - and therefore the more wiggly the path - so further supernovae would appear to be accelerating away from us as an ever increasing rate simply by virtue of the fact that we are in effect straightening the wiggly path the light has take (dotted line)



Just a thought like biggrin


Edited by Moonhawk on Friday 1st April 01:48

Monty Python

4,813 posts

203 months

Friday 1st April 2016
quotequote all
don4l said:
Dark energy is nothing more than a construct to explain away the fact that the universe appears to be expanding at an increasing rate.

Dark matter is also a construct to explain why galaxies are rotating faster than they should.

The reality, IMHO, is that Einstein was not 100% correct, but scientists do not like to admit that they just don't know.

If we look back into history, every generation had complete confidence in their scientists/religous leaders. Yet, we can see that every previous generation were wrong about almost everything.

How come we are lucky enough to be the first generation where the scientists really have discovered the truth?
I find it quite the opposite - a good scientist says they don't know - the bad ones try to blind you with BS.





Edited by Monty Python on Friday 1st April 12:34

Derek Smith

Original Poster:

46,327 posts

254 months

Friday 1st April 2016
quotequote all
Moonhawk said:
One thing that occurred to me.

The accelerating expansion of the universe interpretation is based on the fact that distance is measured by red shift and that supernovae at higher red shifts are fainter than we expect them to be - indicating they are further away than expected if the universe was expanding at a steady rate or even slowing down.

But have the models assumed the light has travelled to us in a more or less straight line?

We know that gravity bends light. Could the fact that supernovae are fainter than expected simply be explained by the fact that light from more distant sources will have simply travelled further by following a more wiggly path around the gravitational fields of all the stuff between it and us and therefore lost more light in that journey than it's red shift distance would suggest?

The further away the supernovae - the more stuff there is between us and it - and therefore the more wiggly the path - so further supernovae would appear to be accelerating away from us as an ever increasing rate simply by virtue of the fact that we are in effect straightening the wiggly path the light has take (dotted line)



Just a thought like biggrin


Edited by Moonhawk on Friday 1st April 01:48
Perhaps dark matter slowed it.