Dark Energy?

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Profile tullio
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Message 1354408 - Posted: 7 Apr 2013, 14:53:30 UTC - in response to Message 1354406.  

Thanks Tullo that link answered what would have been tomorrows question and information being lost in black holes .

So what do you think Dark energy and matter are ? a Higgs particle or anti Higgs field ? or something that yet needs a name

I think we must wait some more time. The AMS-2 experiment on the ISS is scheduled to go on for another twenty years. As for dark energy, I have more doubts. But I don't aspect to learn the conclusion in my lifetime.
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Message 1354410 - Posted: 7 Apr 2013, 15:01:07 UTC - in response to Message 1354408.  

MMM 20 more yrs dag nab it i'll be 70 by the time it's finished or dead
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Message 1354432 - Posted: 7 Apr 2013, 16:57:30 UTC - in response to Message 1354410.  

MMM 20 more yrs dag nab it i'll be 70 by the time it's finished or dead

I am 78 now and 98 is frankly too much. But, as a Pope has said, let us not put limits to Divine Providence. Rita Levi Montalcini died at 102 and my hometown (Trieste) fellow citizen Margherita Hack, an astronomer, is approaching 100. Astronomers live long lives since their spend most of their nights in cold telescope domes watching the sky. I've read of a 100 years old Palomar astronomer who still took his turns at the telescope.
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Message 1354441 - Posted: 7 Apr 2013, 17:32:58 UTC - in response to Message 1354229.  

John, good to see you back at the keyboard. How is the book going?
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Message 1354499 - Posted: 7 Apr 2013, 21:49:43 UTC

Tullo I hope I get to your age .Sorry I didn't reply it was very late here in oz and i'm comeing down with I hope is only a cold so I went to bed .Seeing as your astrominer (sorry I can't spell for shit) how accurate is Hubbles finding that the universe is expanding as I have a big of trouble with how you guys know it's speeding up .Normally you need to watch something over a period of time and then mesure the distance and you get the speed . Looking at a star and see the red or blue shift ! , how does that tell you the speed . I'm a little sceptical that this is accurate enough to give the right answers

So you know I'm only a common bloke with high school education no uni training but I have been fascinated with phiyics , astronomy ,and the big questions ever since I was a boy and only know what I have read or watched in doco's so this is a real treat to actually talk to a astrologer I 'll try a not bug you with to many stupid questions everyday
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Message 1354546 - Posted: 8 Apr 2013, 3:47:14 UTC - in response to Message 1354499.  


So you know I'm only a common bloke with high school education no uni training but I have been fascinated with phiyics , astronomy ,and the big questions ever since I was a boy and only know what I have read or watched in doco's so this is a real treat to actually talk to a astrologer I 'll try a not bug you with to many stupid questions everyday

I think they use supernovae as "standard candles" in faraway galaxies and, by measuring their luminosity they can get the distance of the galaxy. If it is greater than what it should according to the Hubble they infer that the galaxy is speeding away. But I am not an astrologer, just a pensioned physicist.
I am going away for two weeks on the Riviera Ligure (Finale Ligure) so I won't be able to answer your questions for a time. Ciao.
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Message 1354562 - Posted: 8 Apr 2013, 4:54:50 UTC - in response to Message 1354546.  

Thanks for answering Tullo I don't get to chat to many physic people so it still great to talk to you anyway . Have fun on your holiday and thanks again
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Message 1354630 - Posted: 8 Apr 2013, 11:46:03 UTC - in response to Message 1354441.  

John, good to see you back at the keyboard. How is the book going?

betreger,
Thanks for asking.
Progress is slow on the book. But the research continues, non stop, full steam ahead. I'm very thorough and i will make sure that all of my research is 100% before publishing.

John.
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Message 1354699 - Posted: 8 Apr 2013, 16:05:49 UTC - in response to Message 1354691.  

The AMS-2 experiment on the ISS is scheduled to go on for another twenty years.

USA funding for the ISS ends in 2020, in 7 years time. Experts say the ISS may have a physical lifespan up to 2030, before it has to be de-orbited.


This is why I like many others think that earth's orbiting space station should be on the moon. Getting to and from the moon isn't that much harder than LEO and you don't have to worry about it falling out of orbit. Also, if funding dries up for a while, all the hardware will still be there when the decision is made to start things up again. Sorry about the topic diversion.
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
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Message 1354739 - Posted: 8 Apr 2013, 18:01:24 UTC - in response to Message 1354699.  

yes it's relatively easy to get to the moon. However, the cosmic rays would deter any long term says there. NASA or someone would need to develop sheilding that not only blocked cosmic rays and the micro meteors that are constantly bombarding the surface


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Message 1354822 - Posted: 8 Apr 2013, 22:10:21 UTC - in response to Message 1354739.  

Would cosmic rays realy be a problem ? What if most of it was buried and few meters under the surface and only say the landing area was above it . As I stated in climate change it mite even pay for itself if you mined the Helium 3
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Message 1357233 - Posted: 15 Apr 2013, 15:57:37 UTC

Here's a beautifully clear (but shallow) explanation of the first results from the AMS experiment running on the ISS:


A Whiff of Dark Matter on the ISS

... the Alpha Magnetic Spectrometer, a particle detector operating onboard the International Space Station since 2011, has counted more than 400,000 positrons, the antimatter equivalent of electrons. There’s no danger of an explosion, but the discovery is sending shock waves through the scientific community.

"These data show the existence of a new physical phenomenon," wrote Ting and colleagues in an article published in the Physical Review Letters. "It could be a sign of dark matter."

The Alpha Magnetic Spectrometer (“AMS” for short) was delivered to the ISS by the space shuttle Endeavour on its final flight in May 2011. In its first 18 months of operations, from May 19, 2011 to December 10, 2012, the AMS analyzed 25 billion cosmic ray events. Of these, an unprecedented number were unambiguously identified as positrons. ...



Keep searchin',
Martin


Sorry for the NASA-speak!

AMS: Alpha Magnetic Spectrometer

ISS: International Space Station
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Message 1357520 - Posted: 16 Apr 2013, 13:00:17 UTC

Meanwhile, at another extreme deep in the dark underground:


Dark matter experiment CDMS sees three tentative clues

Researchers have revealed the first potential hints of the elusive material called dark matter at an underground laboratory in the US. ...

... Nevertheless, given the feverish pitch of the hunt for dark matter - in other underground labs, at the Large Hadron Collider in Switzerland, and even in space - these three early hints have caused a stir at the meeting.

"It's certainly something we want to be investigating," CDMS collaborator Blas Cabrera...




All good real science with multiple different experiments independently converging to together cooperatively find The Answer :-)

Keep searchin',
Martin


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Message 1364685 - Posted: 5 May 2013, 6:38:43 UTC - in response to Message 1357520.  

Still unknown what this dark matter is actually made of, but whatever it is, it's something new. Physicists already have ruled out every known particle.


Dark Matter Detector To Search For Evidence In Tiny Bubbles


The search for dark matter has been heating up over the last year or so. First, researchers using the Fermi Gamma-ray Telescope announced that a preliminary analysis of the soft gamma-ray data suggested evidence of dark matter annihilations coming from the galactic center.

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Message 1364917 - Posted: 5 May 2013, 19:12:48 UTC
Last modified: 5 May 2013, 19:16:17 UTC

Some things to consider on the subject that are perhaps confusing. Einstein thought that the Universe was static--hence the mistake over the infamous constant. This was what became to be called the Hubble constant which was most recently established at 69.32 ± 0.80 (km/s)/Mpc (or 21.25 ± 0.25 (km/s)/Mega-lightyear).

I don't know if this adressess the question of dark energy which was suggested by the apparent fact that this expansion is speeding up. This is done by observing the Doppler red shift of the more distant galaxies.

Well, two things bother me. One is that I might expect light from the farthest galaxies to travel through more inter-stellar gas thereby causing it to lose energy and hence lower it's frequency.

Also the farthest galaxies are showing us what happened 13 billion years ago which was closer to the big bang than right now. These galaxies 13 billion years ago would be moving faster since the drag of gravity would not have had time to slow them down appreciably after the initial big bang and effects of inflation on the early universe.

I haven't had a formal course in astronomy or cosmology so someone out there may be able to shed some light. If not then I may have to join my son Johnney Guiness in his belief that there is no such thing as dark energy. As for dark mass, I say let's send a probe to bring some of it back.

Another good scientific ?? rant by Daddio.
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Message 1365084 - Posted: 6 May 2013, 10:13:37 UTC - in response to Message 1364917.  

The AMS-2 experiment on the ISS has collected data on possible dark matter. What it has seen so far is an excess of positrons, as other experiments have already seen, such as Pamela. Prof Ting is very cautions about its data and the experiment should go on for all the remaining lifetime of the ISS.
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Message 1365089 - Posted: 6 May 2013, 11:12:23 UTC - in response to Message 1365088.  

Not using miles, 67.3 km/s is 2,422,800 km/hour. The speed of light is 300,000 km/s.
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Message 1365232 - Posted: 6 May 2013, 18:55:12 UTC - in response to Message 1365224.  

Or am I not understanding things correctly?

Nope I wasn't at all! I was rushing out of the house to a meeting when I typed that and didn't have my thoughts straight. Of course the speed of light is 186,000 miles/second NOT mph. Just forget my last post it is a load of rubbish and I should have realised that at the time. Sorry folks. :-(

But then again

Not using miles, 67.3 km/s is 2,422,800 km/hour. The speed of light is 300,000 km/s.


Surely, 67.3 km/s = 242,280 km/hour? I think you also had an extra nought there!

Shall we both start again ? :-)



You are right.
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Profile William Rothamel
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Message 1365268 - Posted: 6 May 2013, 21:03:38 UTC - in response to Message 1365088.  

The speed of light is 186,000 miles per SECOND. This is roughly 3 x 10^10 cm per second. Parts of the Universe are moving away from us at faster than the speed of light due to the expansion of space. This is part of the confusing things about cosmology.
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Message 1365288 - Posted: 6 May 2013, 22:29:04 UTC - in response to Message 1365268.  

The speed of light is 186,000 miles per SECOND. This is roughly 3 x 10^10 cm per second. Parts of the Universe are moving away from us at faster than the speed of light due to the expansion of space. This is part of the confusing things about cosmology.

Quite correct. Called inflation. We know there is stuff past the edge of the observable universe.

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