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Old 12-02-2016, 06:25
Ber
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Sorry, the Daily Mail says otherwise - http://www.dailymail.co.uk/sciencete...s-nothing.html

(Article & comments are hilarious)
Do gravitational waves cause cancer?
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Old 12-02-2016, 11:16
The 12th Doctor
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I wonder what this monumental discovery will do for the search for the Theory of Everything? Gravitational waves clearly aren't acting like quantum physics would predict - their existence surely suggests a smooth, continuous spacetime? Unless LIGO will carry out experiments to test any possible granularity to spacetime the signals might betray. I seem to recall an experiment a while back to test spacetime granularity failing to find any though.
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Old 12-02-2016, 11:28
njp
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Gravitational waves clearly aren't acting like quantum physics would predict - their existence surely suggests a smooth, continuous spacetime?
I don't think anything has changed here. Gravitational waves appear to be behaving exactly as General Relativity predicted, although of course it's early days, given that this is the first direct observation. More detailed tests of the theory will follow.

But that still leaves us with the problem of reconciling GR (essentially a classical theory) with quantum mechanics. If the quantum gravity theorists predicted something different, then they need to rethink their theories. But I'm not sure that any of them did predict anything different!
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Old 12-02-2016, 11:41
Fizzbin
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Do gravitational waves cause cancer?
They might help us to one day visit cancer.

(the constellation)
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Old 12-02-2016, 11:48
Heston Veston
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Has the Pope commented yet?
"God farted"
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Old 12-02-2016, 13:39
Keyser_Soze1
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A brief change of subject.

An excellent in depth article about the JWST from Scientific American.

http://www.scientificamerican.com/ar...e-takes-shape/
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Old 12-02-2016, 15:47
FIN-MAN
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A brief change of subject.

An excellent in depth article about the JWST from Scientific American.

http://www.scientificamerican.com/ar...e-takes-shape/
That was a good read. When people ask why we waste money on space, this from the article is a great reason to throw back at them.
" In some cases, Webb’s builders had to develop new technology just to confirm other new technologies worked, like the cold-resistant optical systems for monitoring mirrors inside cryogenic tanks, or the laser metrology platforms that measure and guide the precise sculpting of mirror surfaces during polishing."
The amount of research and new inventions that happens during these endeavors is what helps push modern society forward.
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Old 12-02-2016, 16:00
Grouty
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RIP Philae
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Old 12-02-2016, 17:41
Keyser_Soze1
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That was a good read. When people ask why we waste money on space, this from the article is a great reason to throw back at them.
" In some cases, Webb’s builders had to develop new technology just to confirm other new technologies worked, like the cold-resistant optical systems for monitoring mirrors inside cryogenic tanks, or the laser metrology platforms that measure and guide the precise sculpting of mirror surfaces during polishing."
The amount of research and new inventions that happens during these endeavors is what helps push modern society forward.
Exactly - some people are only ever bothered about the economic cost of something.

Also the concept of scientific progress and the true value of knowledge for knowledge's sake seems totally beyond them.

But it is priceless.

More on the discovery of gravitational waves.

http://phys.org/news/2016-02-black-h...itational.html

http://www.livescience.com/53697-gra...reactions.html

https://www.youtube.com/watch?v=0uzicC9qujg
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Old 12-02-2016, 22:11
atg
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Sorry, the Daily Mail says otherwise - http://www.dailymail.co.uk/sciencete...s-nothing.html

(Article & comments are hilarious)

The date of it is particularly amusing.
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Old 12-02-2016, 22:18
Heston Veston
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That was a good read. When people ask why we waste money on space, this from the article is a great reason to throw back at them.
" In some cases, Webb’s builders had to develop new technology just to confirm other new technologies worked, like the cold-resistant optical systems for monitoring mirrors inside cryogenic tanks, or the laser metrology platforms that measure and guide the precise sculpting of mirror surfaces during polishing."
The amount of research and new inventions that happens during these endeavors is what helps push modern society forward.
When people ask why we should spend money on science we should ask them what they have contributed to the advancement of the human race, as they're obviously ****ing experts on the subject.
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Old 12-02-2016, 22:53
WhatJoeThinks
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I wonder what this monumental discovery will do for the search for the Theory of Everything? Gravitational waves clearly aren't acting like quantum physics would predict - their existence surely suggests a smooth, continuous spacetime? Unless LIGO will carry out experiments to test any possible granularity to spacetime the signals might betray. I seem to recall an experiment a while back to test spacetime granularity failing to find any though.
What makes you think that?
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Old 13-02-2016, 18:28
FIN-MAN
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Neil deGrasse Tyson Explains Einstein's Gravitational Waves Theory
https://www.youtube.com/watch?v=DoOPEPVYAnU

Some might not like his over the top antics but you can't deny his passion for science is infectious.
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Old 13-02-2016, 19:13
swingaleg
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Neil deGrasse Tyson Explains Einstein's Gravitational Waves Theory
https://www.youtube.com/watch?v=DoOPEPVYAnU

Some might not like his over the top antics but you can't deny his passion for science is infectious.
Yeah, I like him.......he appears in a lot of the science documentaries on Discovery and Nat Geo kind of channels
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Old 13-02-2016, 21:47
KennedyC
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To me the most surprising fact about the detection of gravity waves was in the evidence that they travelled at the speed of light. I always felt that gravitational effects would be instantaneous, acting as the surface through which light and electromagnetic waves travelled.

I suspect that dark matter/energy may turn out to be the paper upon which the universe is drawn.
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Old 13-02-2016, 22:22
njp
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To me the most surprising fact about the detection of gravity waves was in the evidence that they travelled at the speed of light. I always felt that gravitational effects would be instantaneous, acting as the surface through which light and electromagnetic waves travelled.
Instantaneous action at a distance was a Newtonian concept that was abandoned as soon as Einstein's theories gained acceptance. It hasn't been part of mainstream science for more than a hundred years.

Nor is the luminiferous ether about to make a comeback!
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Old 13-02-2016, 23:30
Keyser_Soze1
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Yet more on gravitational waves.

http://www.livescience.com/53707-gra...-it-means.html
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Old 13-02-2016, 23:32
MinaH
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Apparently no one understands quantum mechanics where you can get instantaneous effects across the universe. Apparently it is information that cannot travel faster than light.
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Old 13-02-2016, 23:35
FIN-MAN
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To me the most surprising fact about the detection of gravity waves was in the evidence that they travelled at the speed of light. I always felt that gravitational effects would be instantaneous, acting as the surface through which light and electromagnetic waves travelled.

I suspect that dark matter/energy may turn out to be the paper upon which the universe is drawn.
And coupled with the fact that the ripple has been traveling in space for 1.3 billion years at the speed of light before it hit us. It puts into perspective just the unimaginable size of the universe. Science be cray cray.
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Old 13-02-2016, 23:39
MinaH
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And coupled with the fact that the ripple has been traveling in space for 1.3 billion years at the speed of light before it hit us. It puts into perspective just the unimaginable size of the universe. Science be cray cray.
I think that 1.3 billion years is according to measurements in our reference frame (the earth). If you were surfing that gravitational ripple at the speed of light then it would be much much less than 1.3 billion years.
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Old 14-02-2016, 00:12
FIN-MAN
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I think that 1.3 billion years is according to measurements in our reference frame (the earth). If you were surfing that gravitational ripple at the speed of light then it would be much much less than 1.3 billion years.
Could you please explain in a little more detail what you mean?
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Old 14-02-2016, 00:14
WhatJoeThinks
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Neil deGrasse Tyson Explains Einstein's Gravitational Waves Theory
https://www.youtube.com/watch?v=DoOPEPVYAnU

Some might not like his over the top antics but you can't deny his passion for science is infectious.
Good call. I'm not a big fan of his documentaries but here, ad libbing, he was on great form. +1

I've been thinking a lot about gravitational waves and this video kind of confirmed it. LIGO was essentially a highly-advanced seismometer, but where all of the seismic data has to be removed so that we can concentrate on the 'background noise'. Considering the cacophony that their supercomputers are having to sift through it bodes very well for future space-based gravitational-wave observatories.

The Hubble Space Telescope was a huge improvement over ground-based observatories, even though the atmosphere represents a relatively low-noise medium that adaptive optics can do a great job of attenuating. Even the human eye does a good job of picking stars out of the night sky. Gravitational waves on the other hand seem to be almost lost among the sounds of the Earth. The benefits of sending a GWO into orbit will be enormous.
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Old 14-02-2016, 00:17
WhatJoeThinks
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I think that 1.3 billion years is according to measurements in our reference frame (the earth). If you were surfing that gravitational ripple at the speed of light then it would be much much less than 1.3 billion years.
Could you please explain in a little more detail what you mean?
If I may..

If you were in interstellar space, for example, more time would have passed compared to that measured on Earth. And if you had been travelling along with the wave at the speed of light then no time would have seemed to have passed at all.

Is that what you meant, MinaH?

[Edit] It's fairly meaningless to equate light-years of distance to years of light travel, in my opinion. It completely misses the point that spacetime only conforms to human norms on human scales of space and time. It adds nothing to say, for example, that this distant collision between two black holes happened at the same time that stromatolites were the dominant lifeform on Earth, and it simply isn't true. Simultaneity, especially at such enormous distances, is an illusion. It assumes a universal 'now' that doesn't exist.
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Old 14-02-2016, 00:54
njp
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[Edit] It's fairly meaningless to equate light-years of distance to years of light travel, in my opinion. It completely misses the point that spacetime only conforms to human norms on human scales of space and time. It adds nothing to say, for example, that this distant collision between two black holes happened at the same time that stromatolites were the dominant lifeform on Earth, and it simply isn't true. Simultaneity, especially at such enormous distances, is an illusion.
Well, light years of distance are years of light travel, by definition...

I understand your point about simultaneity being illusory - different celestial observers will disagree about the ordering of these events - but I don't see why this should stop us talking about what was happening on Earth (one specific location) when the gravitational waves from these two distant black holes coalescing embarked on its journey.
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Old 14-02-2016, 00:56
MinaH
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WhatJoeThinks: Yes I think so. There is something called time dilation which means the faster you go the slower are your clocks relative to the "slower" reference frames. So if you were surfing the gravity wave at the speed of light you wouldn't age 1.3 billion years, I don't think you would age at all. But I am not sure you could physically be accelerated up to the speed of light only towards and close to it - so there would be some aging.

So for example super-accurate timepieces have been shown to be behind in time (running slow) after having travelled on the space shuttle or after having taken a number of trips on aircraft.

So for interstellar travel - time dilation would be something relevant to take into account when estimating the ages of the spaceship occupants when arriving at various stellar systems having travelled close to the speed of light during the course of the trip.
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