Orpington Astronomical Society

Astronomy => In the Media... => Topic started by: Kenny on Jan 23, 2015, 09:09:39

Title: Scientists slow the speed of light
Post by: Kenny on Jan 23, 2015, 09:09:39
A team of Scottish scientists has made light travel slower than the speed of light.

They sent photons - individual particles of light - through a special mask. It changed the photons' shape - and slowed them to less than light speed.

The photons remained travelling at the lower speed even when they returned to free space.

The experiment is likely to alter how science looks at light.

http://m.bbc.co.uk/news/uk-scotland-glasgow-west-30944584
Title: Re: Scientists slow the speed of light
Post by: Mac on Jan 24, 2015, 07:12:41
Wow they are slow up in scotland,
the rest of the word has been doing this for 15 years.  :roll:

http://news.harvard.edu/gazette/1999/02.18/light.html (http://news.harvard.edu/gazette/1999/02.18/light.html)

http://news.bbc.co.uk/1/hi/sci/tech/655518.stm (http://news.bbc.co.uk/1/hi/sci/tech/655518.stm)

Maybe they should concentrate on making electrons travel faster then light.
and then claim that discovery as well.

Mac.
Title: Re: Scientists slow the speed of light
Post by: MarkS on Jan 24, 2015, 07:20:49
How interesting.  Could that potentially blow apart the expanding universe theory?

For instance, if it were the case that these slower photons also exhibit red shift then maybe the observed red shift of distant galaxies is caused by the extra amount of "stuff" the photons have travelled through on their journey to us and not by the fact the galaxy is receding?

Mark
Title: Re: Scientists slow the speed of light
Post by: Kenny on Jan 24, 2015, 10:36:06
Quote from: Mac on Jan 24, 2015, 07:12:41
Wow they are slow up in scotland,
the rest of the word has been doing this for 15 years.  :roll:

http://news.harvard.edu/gazette/1999/02.18/light.html (http://news.harvard.edu/gazette/1999/02.18/light.html)

http://news.bbc.co.uk/1/hi/sci/tech/655518.stm (http://news.bbc.co.uk/1/hi/sci/tech/655518.stm)

Maybe they should concentrate on making electrons travel faster then light.
and then claim that discovery as well.

Mac.

:oops:
Mac, as far as my slow Scottish brain can understand, they are completely different experiments. Your links require a vaccum cooled to a few billionths of a degree above absolute zero. The Scots experiment used a mask to slow light which continued at the slower speed once back in free space
Title: Re: Scientists slow the speed of light
Post by: Rick on Jan 24, 2015, 10:55:59
...and quite a few folk else-Net wondering whether the result could be explained by (say) a loose connector, as was (eventually) found in the faster-than-light neutrino experiment a few years back...
Title: Re: Scientists slow the speed of light
Post by: Kenny on Jan 24, 2015, 10:58:32
What is this... bash Scottish people day? Can we not just celebrate the inventive capabilities of a nation that spends most of the year in the dark, rained or snowed on?  :cheesy: :lol:
Title: Re: Scientists slow the speed of light
Post by: Rick on Jan 24, 2015, 11:07:33
It's getting the SlashDot treatment...

http://science.slashdot.org/story/15/01/23/1729231/scientists-slow-the-speed-of-light

Some of it's getting rather technical.
Title: Re: Scientists slow the speed of light
Post by: Kenny on Jan 24, 2015, 11:11:26
Quote from: Rick on Jan 24, 2015, 11:07:33
It's getting the SlashDot treatment...

http://science.slashdot.org/story/15/01/23/1729231/scientists-slow-the-speed-of-light

Some of it's getting rather technical.

The first dozen responses sound like internet trolls.
Title: Re: Scientists slow the speed of light
Post by: Rick on Jan 24, 2015, 12:37:58
As ever, with SlashDot, ignore the trolls, and look for responses tagged informative...
Title: Structured photons slow down in a vacuum
Post by: Rick on Jan 24, 2015, 15:04:59
Structured photons slow down in a vacuum

Now it seems that physicists have come up with a new way of changing the speed of light in a vacuum. Over two years, Miles Padgett and colleagues at the University of Glasgow, together with Daniele Faccio of Heriot-Watt University in Edinburgh, designed an experiment that can determine whether light with a certain "spatial structure" travels substantially slower than regular light in a vacuum. The researchers created a source that emitted pairs of photons simultaneously. One of the photons went straight to a highly precise photon counter, while the other went via two liquid-crystal masks, which imparted their profile onto the passing particle of light.

More: http://physicsworld.com/cws/article/news/2015/jan/22/structured-photons-slow-down-in-a-vacuum