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Physics, Astronomy & Cosmology / Why one Swedish professor doesn´t belive in dark energy

« on: 01/09/2011 15:37:55 »

 I heard on the radio a Swedish Professor of astronomy that said that he did not believe in dark energy.

He believed that the photons emitted billions of light years away lost energy while travelling through space, and since light can’t slow down it looses energy by red shifting. Similar to light leaving a heavy object and gets red shifted.

The farther away from us the light was emitted the more energy it will have lost and the more red shifted it would be giving the appearance of an accelerating expansion of the universe.

It seems reasonable to me that a photon when it has travelled billions of light years will have lost some energy thus getting red shifted.

Have you heard this theory before? Any thoughts on this?   

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Physics, Astronomy & Cosmology / What's happening at the LHC?

« on: 05/04/2011 03:30:02 »

Magnus Westberg  asked the Naked Scientists:
   
Hello Chris and the naked scientists
 
thank you for a great podcast i´ve listened to all your episodes,
 
My Question:
 
How´s it going at the large hadron collider? I hear a lot about what the want to do and find, but have they actually made any scientific discoverys since they started?
 
Magnus Westberg listening in Sweden        

What do you think?

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New Theories / Could the photon be the sole elementary particle?

« on: 25/02/2011 14:42:39 »

What I really like about this theory is that it seems to explain many things, although I´m not smart enought to follow it all it looks really interesting. Do you think there is any way to test this theory in the future by some experiment?

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New Theories / New hypothesis behind big bang that gives an explanation to dark energy & more

« on: 25/02/2011 13:55:58 »

I always like new theories, let´s see if I understood you correctly :-)

Do you mean than when a black hole is created in our universe, It stretches out through some other dimension and creates a white hole in  another universe, and matter is pulled in from each side gets annihilated in the middle and creates our universe?

The expansion of the universe can be explained by the big bang ( explosion throwing everything outward) The problem is to explain why the expansion accelerates, It should be slowing down under gravity. But it is not, does your theory explain that in some way?

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New Theories / Dark energy theory

« on: 17/02/2011 13:28:55 »

3-d hypersphere, I have not heard about that theory can you explain.

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New Theories / Dark energy theory

« on: 15/02/2011 19:22:27 »

I agree bardman, nothingness is impossible to imagine, I don't even know what to call it.

"It would seem the best option to continue increasing entropy relatively easily would be for the universe to grow." -Yes, and maybe this is the force we already experience as dark energy although our universe is far from maximum entropy within.

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New Theories / Dark energy theory

« on: 15/02/2011 18:48:20 »

another way of thinking of it is: if there is absolutely nothing outside our universe the entropy there would be zero, right? inside our universe it is very high, And as we know from I think its the third law of thermodynamics every system wants to increase its entropy. So our universe is sucked out (expanded) to equalize this differens in entropy by "filling the void" Did that make sense?  :-)

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New Theories / Dark energy theory

« on: 15/02/2011 18:23:29 »

I agree i don´t think there is a shell around the universe. But I belief there is a point where our universe ends, where there is no more matter and perhaps no more spacetime. A finite amount of matter was created in the big bang and the matter has only spread so far, 20 billion lightyears or something. Beyond that there is something else, And maybe our universe (all the matter etc) is being sucked in to this something, like a low pressure sucking in air.

I also like the theory of vacuum energy, Maybe we just dont understand yet how it works on extremely large scales

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New Theories / Dark energy theory

« on: 15/02/2011 14:45:45 »

What if the observable mass in the universe is being pulled to a massive shell outside of our light cone?  We live in an egg and we are the yolk.  Can this hypothesis be disproved?

well the most obvious answer is that the net force of gravitational attraction within a uniform shell is zero.  For a force to exist the shell must be non-uniform, yet the expansion we can measure is all pretty homogenous and isotropic

would that not be in support of my theory that the force is coming from  "the outside" I hope so :-)

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New Theories / Dark energy theory

« on: 15/02/2011 14:35:45 »

What if the observable mass in the universe is being pulled to a massive shell outside of our light cone?  We live in an egg and we are the yolk.  Can this hypothesis be disproved?

Yeah something like that :-)


The vacuum energy was found by someone to be 120 times to large to explain dark energy, I think I actually heard that on the naked astronomy podcast but I have no links to the source.

The fact of the matter is that we really don’t know what is beyond our observable universe, and you are right imfataal we can never find out, And I also realize that a theory like this that can not be proven or disproven has little value but I think its an interesting idea to keep in mind, that our efforts to look for dark energy may be futile since it might not be within our observeble universe.

We think that the universe is finite, so something must lay beyond, And we don´t know what that is, but just maybe its pulling us in to it and we interpret this as dark energy.   

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New Theories / Dark energy theory

« on: 14/02/2011 14:56:59 »

well... maybe its crazy to even talk about "something outside the universe" but I figured if the universe is expanding it must be expanding into something, and maybe this void of nothingness outside our universe is actually pulling us outward giving us the impression of being pushed outward. I would like to hear why this could not be the case.

I realize that it would be impossible to prove that there is some force outside the universe other than to prove that it is not inside.

Anyway science have had big problems finding out what dark energy is, the vacuum energy turned out to be wrong and the LHC does not seem to find particles the can explain this force either, and yet our universe is supposed to be mostly dark energy, it should be everywhere. maybe the reason we don’t find it is because the dark energy is really not in our universe at all.

Also I think I heard a theory about bubble universes with our universe being just one of many universes. If that is the case maybe the void in between these universes acts like a vacuum sucking our universe in to it.

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New Theories / Dark energy theory

« on: 11/02/2011 15:17:11 »

Dark energy theory

Hello guys,

I don’t know if anyone have thought of this before or if it's a ridiculous idea, but here is an outside the box theory  []

We think of dark energy as a force that accelerates the expansion of the universe. As a property of space that constantly pushes the universe outward in to the nothingness beyond it.

Is it possible that it is actually “free faling” in to this nothingness. So rather than being pushed from the inside and out, the universe Is being pulled outward in to the nothingness outside our universe

I think this would be consistent of what we “know” about dark energy that it has been acting like a cosmological constant for a very long time and have not been diluted as the universe has expanded because the dark energy is is not actually inside our universe.

If the universe is constantly being pulled out in to the nothingness, “free falling in to it” In the beginning it would have been held back by the matter density (gravity) and as the matter density decreases it would accelerate faster like we also observe.

So dark energy is not a force pushing the universe outward from the inside.
It is something pulling it outward from the outside.

 The universe is expanding and it must be expanding into something, what if this something is actually pulling it outward and we interpret this as dark energy.

I´d love to hear what you think

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Physiology & Medicine / Does not watching TV make you more creative?

« on: 13/01/2011 10:15:30 »

I definitely belive TV keeps people from doing more relevant, educating and important things, no doubt about it! I do it myself aswell. The intelectual level of todays TV is frightingly low. with some rare exceptions of course.

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Physiology & Medicine / Does a fever raise temperature equally over the entire body?

« on: 13/01/2011 10:01:36 »

Hello, When you get a fever your core temperature rises equaly. But the temperature of your skin always differs alot between body parts. thats why body temperature always refers to the "core temperature" since the temperature of for example your hands can be much lower than you core temperature. So if you mesure a persons true core temperature it will be the same everywere. But you can get a much lower temperature reading by failing to do so. 

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Physiology & Medicine / What makes mucus green?

« on: 13/01/2011 09:33:52 »

Nice question, I think the yellow to green color is due to the dead remains of white blood cells and bacteria althoug I do not know exactly what substance it is that produces the color.

Eating your bogies has a salt conserving aspect of course :-) But maybe it´s just a habit we develop when we are babies and like to put everything i our mouth, the salty taste makes us keep doing it to older ages :-)

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Physiology & Medicine / Can low temperatures cause brain damage?

« on: 13/01/2011 09:24:00 »

Not necessarily, only if blood flow and thus oxygen supply gets to low. And of course if ice crystalls begin to form you definetly will get brain damage.

In a real life senario if you get very hypothermic I dont think that you would survive temperatures low enoght to couse brain damage since blood flow to the brain probably is one of the last things to fail

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Physiology & Medicine / Why does lack of sleep cause bags under the eyes?

« on: 13/01/2011 09:15:44 »

Here is my Guess/theory, When you are sleep deprived your blood presure fals, because of low adrenalin and high melatonin levels. To keep bloodpresure from faling to low your body reduces blood flow to periferal tisuses and your skin, the reduced blood flow couses the skin to look pale or blue (just like your lips get blue when you are hypothermic)

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Physics, Astronomy & Cosmology / Re: Is it possible to mix the big freeze and big crunch theories using black holes?

« on: 13/01/2011 09:05:33 »

I think i´ts a plausible senario, unless the universe gets so diluted before it happens that the black holes cant interact. But I guess if they drift around like that for the better part of eternety the will eventually com together...maybe

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Physics, Astronomy & Cosmology / Is infinity what you get when youu place to plan mirrors parallel to each other?

« on: 28/12/2010 12:13:25 »

If the mirrors are perfect i would say yes, but since mirrors are never perfect you will not get an infinite amount of reflections.

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Physics, Astronomy & Cosmology / How do you think the Earth will end?

« on: 22/12/2010 10:24:27 »

The earth will end when the sun becomes a red giant and fries us  [8D]