Physics Gist

Do you know if the Sun was fueled by Gasoline or wood, it would have been burnt out in just a few hundred years, So how it is still here after 4.5 billion years.... Physics!!! The Sun is like a big nuclear reactor in the sky. It is fueled by nuclear reactions that fuse Hydrogen atoms into Helium, other heavier elements and energy (in the form of Photons) in the process. In this way the Sun is slowly converted into mass and energy in the form of sunlight and have more than enough fuel for us for billions of years. But nuclear fusion is not as simple as it looks. Fusion is the process that powers the Sun and the stars. It is the reaction, in which two atoms of Hydrogen fuse together to form an atom of Helium. In the process some part of hydrogen is converted into energy. On earth we need to heat hydrogen hundred times hotter than that of the Sun to set a fusion reaction. Sun has a temperature of 15 million Celsius degrees in its core whereas it requires more than 100 million Celsius deg...

 If we succeed in getting rid of everything from a part of space i.e. from all the planets, stars, atoms, particles, even light and radiation etc, this space still have weight. It turns out that NOTHING is not nothing but it is something. How is that possible? Space is bubbling with virtual particles that pop in and out of existence. These particles do this in such a short time scale so the laws of classical Physics forgives the creation of these ghost particles which seem to come out of nothing. The laws of Quantum Mechanics allow this.  To visualize, consider an empty space within a proton. Since most of our physical world is made up of protons and neutrons, this so called empty space (inside protons) gives mass of proton. "Empty space is actually full of quarks and Gluon Field Fluctuations, so empty space is not empty" (Professor Derek Leinweber, University of Adelaide).  Here is the simple visualization. 0 represents nothing. But 0 can also be expressed as 1+(-1) or 1...

    Matter as we know it, atoms, stars, the galaxies, planets & trees, rocks and us, this matter accounts for less than 5% of the known universe, about 25% is dark matter and 70% dark energy, both of which are invisible. This is kind of strange because it suggests that everything we experience is really only tiny fraction of reality. We really have no clue that what dark matter and energy are or how they work .We are pretty sure they exist though, so what do we know? Dark matter is the stuff that makes it possible for galaxies to exist. When we calculate, what the universe is structured the way it is, it quickly became clear that it's just not enough normal matter. The gravity of the visible matter is not strong enough to form galaxies and complex structures, the stars would more likely be scattered all over the place and not form galaxies. So we know that there is something else inside and around them, something that doesn't emit or reflects light, something dark. Bu...