Recent content by chrisina

I think one issue which seems to be very naively ignored in this thread is the level of scientific litteracy of human beings. Of course, science, when practiced by serious people, that adhere to its methods and accept the scrutiny of peer review, does not constitute per say, a faith based...

thx Marcus, what about the number of free parameters ?

Congratulations Garrett ! Hope you will get suport from as many researchers are needed to make the necessary calculations which will be needed. It is indeed a beautiful mathematical hypothesis, let's hope that it ends up being the real description of nature, at least it's definitely a new...

Danger, indeed gamma rays are just highly energetic photons, but they play a key role as a ionizing radiation (photo-electric effect, pair production and compton scattering) effecting molecular changes for instance in the Earth's atmosphere.

Melz 9, this is what one of the greatest scientists of all times, Ludwig Bolzmann, said in 1875 : "The general struggle for existence of animate beings is not a struggle for raw materials – these, for organisms, are air, water and soil, all abundantly available – nor for energy which...

The reason why an object is floating vs sinking into water is because in the first case (floating) it is in equilibrium, ie the gravitational force of the Earth (which depends only on the mass) is compensated by the opposite buoyancy force produced by the surrounding water (which depends on the...

H8, the distance from the moon where the gravitational influence of the Earth is weaker than that of the moon is as explained and calculated by Marcus, Tony, Janus, 38,400 km. The tricky part is that this is not the distance where an object will start gravitating around the moon...

Hi Marcus, I am going to try to explain how I visualize the 3 sphere. Let me know what you think. It's a purely mental exercise, impossible to draw. Coulours are essential. I start first with the 2 sphere : example the earth. We all know what is the equator, ok ? In your mind, paint that...

I am trying hard to understand what are your "feelings" on the matter of time, but can't. Can you please try to explain them once more ? Thanks

Chronos, totally in line with you. I would add the question, "isn't it a fact that, so far, adding more spacetime dimensions has done nothing in reducing the degrees of freedom ?". Having said that, if we had a theory that could enable to derive the 26 parameters from one, would you say that...

Nariad, thanks for the two articles. However, please note the difference between the two : In my opinion, the second one, by Sean Carroll, gives some good elements of answer to the original question from Liger20. Also, note the sentence : "String theory requires the existence of extra...

This is just a perfect example of press trying to make science claim something that it doesn't want to claim yet.

Point taken Marcus, so let's talk about the size of the overall universe. But how can we discuss this issue without having a validated theory of gravitation that works at Planck scales ? GR, the FRW metric and the Lambda CDM model, associated with the measurements of the various omegas...

The problem, Marcus, is that as we get closer to 1 on the measurement of Omega, a very small % error makes the estimate on the radius of the Total universe increase by a huge amount. So I think its best to focus on lambda CDM model with omega = 1 (0,3+0,7), and the two radiuses that have...

BTW, Sean Caroll did point this out in his blog : "Why in the world would we expect a homogeneous expanding cosmology to emerge from the other side?" And this is Lee Smolin's reply (towards the end of the Blog) : "There is another issue, which is whether generic states before the...