skaltezon

That sounds about right, since we've assumed the existence of dark matter from the gravitational effects in the first place.

Krauss/Scherrer's concern for our descendants' ability to construct an accurate cosmology 100 billion years from now is laughably optimistic about the more immediate problem of our sun's approaching 'red giant' phase a mere 5 billion years from now.
Computer simulations suggest we should find another planet to hang out on before we get toasted and ultimately swallowed.

Hope dims that Earth will survive Sun's death - space - 22 February 2008 - New Scientist

Or 'we' could be taken to mean any intelligence from our intergalactic family of the merging Local Group whose descendants will be around to ponder cosmological niceties long after evidence of the rest of the universe has slipped over the event horizon.

Sagan/Shklovskii's Intelligent Life in the Universe is a good read.

VEGANGELICA

Thank you for the information and the link to the Krauss lecture, which I watched several days ago.

I agree with you about his lecture, by the way.

I felt that Krauss explained the science of the universe's expansion very well, such that a layperson like myself could follow most of it. However, he flung out a lot of jokes based on insults that targeted religious people, and there was no need for him to do so.

For example, he said, "Forget Jesus! The stars died so you could be here today," while describing his wonder that the heavier elements in our bodies resulted from fusion during the death of stars (which is indeed a wonderful realization).

If he wished to make the distinction between scientific and religious thinking, he could have done so by describing those differences without the insults. He also could have acknowledged that many religious people still feel there is mystery and wonder in the universe and its origins, just like he feels.

He seemed overly ready to leap to his own conclusions based on the science. For example, even though learning that our universe appears to be "flat" (the angles of a gigantic triangle still add up to 180 degrees) means that our universe could have originated out of nothingness and out of zero energy, this tells us nothing about whether or not religious views of the universe's origins are correct, yet Krauss seems to conclude that it does.

Finally, he erred twice by claiming, as if it were fact, that life *has* emerged many times in the universe. For example, he said, "Rare things happen all the time, including life." (I was taking notes.) I found it ironic that he made such a statement, because he had just faulted religions for providing answers to questions inappropriately, yet then he did so himself since he doesn't know that any aliens exist. He should have acknowledged that we have no evidence of any other lifeforms existing elsewhere instead of stating they do as if it were fact, especially since he had just said that "scientists love not knowing!"

Krauss did, however, make some jokes that were funny and not too hurtful, I felt. These were a few playful jokes aimed at biologists and non-mathemeticians such as myself.

I especially liked his humor when he said, "Using the miracle of modern mathematics, you can rewrite that equation," before showing how the cosmological term can be moved impressively from one side of an equation to the other by adding it to each side.

He also showed a cute cartoon of two cowboys on horseback watching a distant train, which was his segue into an explanation of the redshift in microwave radiation that has occurred during the universe's accelerating expansion. One of the cowboys said, "I love hearing that lonesome wail of the train whistle as the magnitude of the frequencies of the wave changes due to the Doppler effect." I thought that was amusing.

All in all, I felt it was a good, clear lecture in terms of science, but Krauss mocked religious viewpoints while falling prey to some of the very faults he ascribed to religious thinking.

Yes, my interpretation is that Krauss and Scherrer know all life on earth is toast, and so they were not talking about our descendents. Instead, they were considering the conclusions that potential alien astronomers many years from now on other planets in our galaxy may be able to draw about our universe's origins as evidence of the Big Bang becomes undetectable.

The focus of the Krauss/Scherrer article on the viewpoint of future alien civilizations made the article poignantly sad but beautiful to me, because it shows how the authors can appreciate our brief explosion of awareness and life while knowing it is doomed. Despite the unpleasant future we earthlings face as predicted by science, these cosmologists still have the presence of mind and imagination to consider the welfare of future alien civilizations who will be following their own similar journey of scientific discovery about our universe's history.

The Krauss/Scherrer article reminds me of a news story that struck me when I heard it as a child. A trapeze artist performing without a net fell during her act. Knowing she was doomed, she had the presence of mind to perform a swan dive right to her very end. I admire cosmologists who show similar grace by trying to understand as much as they can about our own future demise, and take pleasure in living and thinking even without any promise of a cosy, happy ending.

My view of the heroic cosmologist, thinking about the origin and future of the universe while plunging into oblivion:

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jackhammer

Despite a lack of mathematics in the programme, I think this is well worth a watch especially the last 15 minutes regarding M theory and a possible explanation for the big bang which does sound feasible on paper and at leasts gets rid of the 'something out of nothing' albatross that clings to the big bang.

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VEGANGELICA

^ I will watch this, but first I want to say that I just read a report published online today of a black hole caught for the first time in the act of swallowing a star!!!

Black hole caught in act of swallowing a star - Technology & science - Space - Space.com - msnbc.com

I then read on this National Geographic website about the possibility that a black hole can spawn a new universe, a hypothesis I had heard before but haven't read much about:

In honor of the supermassive black hole Swift J1644+57 eating a big star, I will post the following song, even though I know some people would like to see it consumed and destroyed in the supermassive black hole that is its title.

Muse - "Supermassive Black Hole"

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skaltezon

I'd be interested in how this sounds feasible on paper to an auto mechanic.

A fantastic story of multiverses colliding in the 11th dimension, concocted by three physicists on a train ride of less than an hour on the way to see a play.

The upshot is that our universe's 'big bang' was the contact of brane ripples between colliding other-universes.

And in the last moments of the program, the once-affable Alan Guth (originator of the inflationary universe theory) turned Mad Scientist:

Buah ha ha. Coming soon: vacations in alternate universes.

This program aired on BBC Two at 9.00pm Thursday 14 February 2002.
Read the transcript here:
BBC - Science & Nature - Horizon - Parallel Universes - Transcript

A more recent 'Horizon' production, "What Happened Before the Big Bang?", that was first aired on October 11, 2010 examines several other current theories that attempt to look past the Big Bang. I've seen it, but BBC has put a copyright block on all online videos of it.

Nevertheless, here's a pretty good summary of the program from vixra.org:

You can follow the program from the transcript, which can be downloaded here:
http://www.google.com/url?sa=t&sourc...JxF2fg&cad=rja

A list of BBC's 'Horizon' series of science programs over the years can be found here:
List of Horizon episodes - Wikipedia, the free encyclopedia

right-track

CERN says a neutrino beam fired from a particle accelerator near Geneva to a lab 454 miles away in Italy, travelled 60 nanoseconds faster than the speed of light.

Discuss...

jackhammer

Yeah I caught this earlier today on BBC website and although your first reaction may be like What? That's impossible but just because we seem at a very advanced technological state, it doesn't mean that a near 100 year old theory is wholly correct.

There is a long way to go into figuring stuff out and maybe we will never will and maybe that should be the way it is. Once one problem is solved there will always be another right around the corner.

It has also been suggested this week that 'dark matter' is not an easy prefix on which to attach everything onto that we can't figure out because after 10 years of searching we have not come across one single particle.

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sonar1

Humankind can only glimpse a tiny part of the whole of this Universe and conclude that it consists of matter and energy, and that at some point there's no difference.

As we move off the planet and into different perspectives (as example the gains in knowledge already afforded by The Hubble telescope, and various probes that have been sent out, etc)), I suspect today's revelations will be dropped in favor of new ones which will possibly reveal that we're doing the things the hard way with CERN, etc.

Nevertheless it is the process we have, so we follow it until the technology becomes obsolete due to discoveries yet to be understood or even suspected as yet.

I find the quest for this understanding fascinating, and salute those who have dedicated their lives to understanding the physical "reality" we find ourselves operating in as beings.

There seem to be levels of understanding that are very difficult to transmit to the general population.

Stephen Hawking, et al, think in math.

I think in English. So right away there are things I'm not going to understand that they are fluent in.

sonar1

Lately I've been contemplating an image that sometimes accompianies shows like The Universe, on the History Channel, etc.:

They sometimes show a pulsating glob of gold colored stuff that then expands exponentially into the known Universe (as everything there is).

My concept is this:

We think of "nothingness" as possessing the physical attributes of a vacume. If that were accurate, it then becomes just as feasible to describe that the strength of this vacume of nothingness "pulled" the universe into existence, and supports its expansion.
Sort of like Bernulli's principle of cavitation pulling the oxygen out of water by lowering the pressure in the pump below the boiling point (gas laws).

Two problems: the first is that scientists have been demonstrating that the expansion of the universe is "accellerating" as we observe further and further away from us, towards the theoretical "edge" of the expanding universe. How that could be if the vacume were doing the work without increasing its pull kind of smokes my melon. 'Course the outer edges of explosions don't accelarate faster later either. Physics has got some secrets we ain't hip as we think we are to, yet.

The other is that what is present in the universe as matter was implied (at least in energy) at the beginning. Which I suppose crashes my theory about the vacume being The Cause.

Ever grow crystals for a Junior High Science project?

It just looks like a pan of colored water when you heat the ingrediants, but as the days pass crystal structures form and grow and soon you have hard material.

So when I think of "all the ingrediants being present" at the big bang moment, I conceive of that potential in somewhat the same way.

Of course a mathematician could easily point out my fallacy, and demonstate that my theory is way off.

In the same way, I assume all our present theories will some day be shown to be way off.

Guybrush

Before I read the rest of the post, I think you got things the wrong way round. A vacuum, like that you can create inside a cup, doesn't really pull at things. It's matter that pushes. Stuff is being pushed in because of gravity.

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Something Completely Different