11 replies to this topic

[ARSEN]

I think it's amazing subject. 70% of our world made up of dark energy and another 25% made of dark matter. Our eyes can only see things that reflect light and these accounts for only 5% of our universe. Dark matter is every where around us. Billion of particles go through earth and our bodies every day. Without dark energy we would never exist, dark energies keep solar galaxies intact.


Alex Filippenko is amazing.

[Kuech Da Sneak]

It's always interesting to see the reaction on someone's face when they realize how small the amount of matter we can actually see is in relation to our universe.
Now to only invent a device that can tangibly & freely detect both dark matter & energy.

[cotblock]

What would you think if the dark energy had consciousness? http://www.robertlan...f-the-universe/

[ARSEN]

You know sometime when you hit your head very hard you see some strange things fly around for few seconds until our eyes adjust. Always wonder if our brain see dark matter particles for this few seconds because it looks so real.

[ARSEN]

Also, what if our soul consists of dark energy? So when we die this energy is given back to universe. We cannot see this energy but we know its there.

[venom]

I approve of this thread as well

[Kuech Da Sneak]

You know sometime when you hit your head very hard you see some strange things fly around for few seconds until our eyes adjust. Always wonder if our brain see dark matter particles for this few seconds because it looks so real.

Just your neurotransmitters going full retard, but that would be awesome if it were at all possible.

[venom]

You know sometime when you hit your head very hard you see some strange things fly around for few seconds until our eyes adjust. Always wonder if our brain see dark matter particles for this few seconds because it looks so real.

Haha ive wondered about that as well.

[chris999]

I'm still not to sure what to think about dark energy. No one has any idea what dark energy is, if it is really even exists.

They basically came up with the term "dark energy" when scientists noticed that the Universe is expanding more rapidly than was expected due to the mathmatacal equations that derived from the single point of mass theory, or the "Big Bang".

What is most troubling about it is that the cummulative gravity of all of the mass of the universe has spread through space faster than scientists realized. Thus, they think that the entire universe must weight 70% more than just what we can see with our various telescopes.

I tend to believe that there may be a problem somewhere with the mathematics, which basically means, historically, that they are probably barking up the wrong tree right now, and they need to take a step back, and look at something else for a while, and try to gain a different perspective.

So far as I can tell, right now they may need to try and start figuring out quantum mechanics. That is where we are going to find more of the answers that we are looking for, not in deep space. I also dont think that we even have the capabilities to understand anything else about the universe, until we figure out more about the world at the sub-atomic levels, which right now seems to be crazier than anything we could have imagined.

[ARSEN]

There is lots of evidence of dark matter, although many would only consider a "smoking gun" proof to be a direct detection of dark matter (e.g. an observation of dark matter particles colliding, or their production in the Large Hadron Collider). One of the most compelling single pieces of evidence for dark matter is the "bullet cluster" (see reference). In the bullet cluster, most of the mass in the system is not where the gas is, and the mass of the stars themselves is quite small, so that means something invisible comprises the mass (i.e. dark matter, by definition).

Other pieces of evidence of dark matter are (1) the high speeds observed in galaxies and clusters of galaxies (this was the original reason it was proposed), and (2) observations of the cosmic microwave background and the large-scale structure of the Universe (the distribution of galaxies) need more mass than we can account for with the normal matter.

The dark energy thing is dicier. Dark energy is synonymous for most scientists with cosmic acceleration, i.e. the statement "there is dark energy" usually means exactly "the universe's rate of expansion is increasing," without reference to what this dark energy stuff actually is. (By contrast, we're pretty sure the dark matter is made up of actual massive particles)

The evidence for dark energy is compelling. The cosmic microwave background (CMB), large-scale structure, observations of supernovae in faraway galaxies, and the cross-correlation of the CMB with the large-scale structure (seehttp://ifa.hawaii.ed...owave/supervoi… for example) all indicate cosmic acceleration. However, it might fall short of a "proof" for you until we actually understand what's causing it. Dark energy may not be a substance at all, but perhaps a quirk of how our Universe works.

As for your question "could the equations just be wrong?" of course the answer to that is always yes (several people do seriously study "MOdified Newtonian Dynamics," for example), but there are so many different observations that fit with our current picture, that almost all cosmologists accept it, even if though it's definitely troubling that we don't really understand what causes dark energy. Sure, there are a couple of rather ad-hoc parameters (the densities of dark matter and energy), but no other theory that we know of comes close to explaining all the observations.
Source(s):

http://en.wikipedia....ki/Bullet_clus…
http://ifa.hawaii.ed...owave/supervoi…


Read more on this topic
http://answers.yahoo...07082449AAhpWzd

[chris999]

Nice reply. Seems like they have made some recent ground lately. I have always had a love of astronomy, and quite oftem i like to cick through the headlines and see what the newest experiments and data are. I was not familiar with the "Modified Newton Dynamic". Is that some kind of modifications to his equations or something? Interesting.

But anyway, the WMAP data has been around for a while now, but it looks like they are starting to be able to figure out just how much to untwist the gravitational lensing, and are starting to come up with a workable formula which will be able to more accurately detect the amount of gravity that is located in these different superclusters and voids.

I am guessing that with a little bit more accuracy, they will be able to have a closer estimate as to how much of the gravity of the universe actually is dark matter, and hopefully it wont be 70+ percent. I am also interested if learning how much, if any, gravity is coming from the voids between the superclusters. Maybe no visible matter there, but could be filled with 10 to the hundreth power sub-atomic particles flying around.

[King]

Dark energy is not a bogeyman.

The second law of thermodynamics is more dangerous than that nonsense.