# Gravitational waves

Hi,
before I start to write about gravitational waves, let me explain how electromagnetic waves work.

Electromagnetic waves are just light which we see from candle for example. The thing is that in such a candle atoms oscillate and in the process of burning electrons are jumping on more energetic levels, orbitals. When this happens they want to go back right away, so they emit photon and fall back on the lower orbital. Such a photon then travels towards you and you can sense it with your eye.

But all of those atoms oscillate because there is huge temperature in the candle (800°C). They move back and forth creating waves of photons because some photons are closer together as the atom moves to the maximum of oscillation. As it goes back the photons are more stretched apart creating the gap in the wave. This is called electromagnetic wave.

If you had really good eye and somebody would walk away from you with candle, the light would not stop but you would observe the light come towards you in wave, in quantum. The frequency would get smaller and smaller but it would never disappear and would always appear with the same luminosity.

Now when you have gravity this can happen too in what is called gravitational wave. Such a wave is a result of shaking with something that interacts with gravity. The problem here is that gravity is such a weak force that you just can not observe it on candle and you need some kind of star.

Here comes two neutron stars which were found to be rotating rapidly around each other. As they rotate they create the ripples in space time, gravitational waves. In 1993 the Nobel prize was awarded to two guys who were able to indirectly observe how this system of two neutron stars was losing energy emitting those waves, they were observed to be slowly getting closer and closer to each other.

Physicists are trying to observe gravitational waves directly with tremendously precise methods using lasers but it was not yet achieved.

Dragallur

Picture is from here.

# How does particle accelerator work?

Hi,
so as I continue with the book I am reading right now about particle physics I will write about the basics behind particle accelerators.

There are several types of accelerators, they can be divided into groups by either the energy they can create or what kind of particles they are colliding, some accelerators even do not have this circle but they rather just hit some big target.

Inside accelerator you will surely have some great detector which is going to collect the data for you. In Large Hadron Collider (LHC) in CERN there are two main detectors: ATLAS and CMS. There are two so you can compare their results.

Those detectors are huge, ATLAS has 21 meters in diameter.
Then there is the tube in which you have got those particles running. In LHC there are protons in both direction. Those protons are taken from little bottle with hydrogen, this bottle would serve for billions of years because there are 10^27 particles inside.

When you take these particles you will speed them up. The particles in LHC those are protons are separated to groups. Between each group is seven meters of vacuum. In each of those clouds of protons are 100 billions of protons. This cloud can get thin as 1% of millimeter right before collision.

Protons are all positively charged so it is hard to keep them in the cloud. Because of their charge, you can speed them up using magnets. To get the top speed you have to use extremely strong magnets, which means electromagnets [1]. Those magnets will speed the particles to 99.999996% of speed of light, so obviously that is where theory of relativity comes to role, for example those particles are not spheres but rather pies because of their huge speeds — effects of relativity.

After you speed up those particles you are going to collide them. This happens at the detectors which are going to measure all the stuff that is flying away from the collision. You may identify particles by their direction of traveling, by this you may know their charge. Also how deep they were able to fly. Mions for example have longer life times than most other particles so they are able to fly through the accelerator, while bosons w and z or tauon have such a low life time that they wont fly very far and most of the time you are going to observe their products rather that those particles alone.

Dragallur

[1] Electromagnets are magnets powered by electricity because when you have electricity, it creates (electro)magnetic field. This gets stronger the stronger is the current. In particle accelerators it can get so strong that the magnets would melt at a moment because of friction with electrons, that is why they must be cooled to little over absolute zero, using liquid helium.

Only picture

# 5) Four fundamental forces: Strong interaction

Hi there!
I am back again! I was very sick with great temperatures but now I am alright with idea what to write about so I am bringing probably the last post for four fundamental forces today with strong interaction as the strongest of all forces.

Again on the left I have here proton. There are two parts of strong interaction, first is color force which is the stronger one and it holds particles, like hadrons (particles made of quarks) together. You probably heard of colors of quarks, there is green red and blue (RGB) and in such particle like proton or neutron those colors always have to add up to white color. If it would be antiparticle it would have anti red, anti green and anti blue.

Again on left you can see how these colors add up to white. Well what happens is that there is gluon, particle which is carrier for strong interaction and it jumps from quark to quark and when it touches it changes its color. There is great animation in this video, I recommend to watch it: https://www.youtube.com/watch?v=BNDOSMqGLlg
This color force is extremely strong so it does not let quarks to go apart. It is even that strong that when you break it new quark will be created from that huge amount of energy! Scientist think that right after big bang when particles were really fast and close to each other there was state of matter called quark-gluon plasma which was kind of soup of quarks and gluons. It is hypothetic and it was not yet created in LHC or somewhere else.

There is that second part of strong interaction called: nuclear force. I am not really sure about it, but anyway you maybe wondered why does nucleas exists when protons(+) should repell each other and that is made by particles called pions which are carrying quarks around and they are creating reaction which is attractive.

On the end, pions are particles made up of two quarks but one of them has to be antiquark so they looks like this:
There are three types of pions and those are Pi+, Pi-, Pi 0. Their life time is incredibly short and they are decaying to neutrinos or gamma rays.

That will be all,
Dragallur

# 4) Four fundamental forces: Weak interaction

Hi guys!
We are nearly finishing posts for fundamental forces. First I would like to apologize that I forgot to mention that force carrier for Electromagnetism is photon.

So weak interaction is pretty weak but still insanely stronger than gravitation. It works with quarks and their flavors and it is responsible for decay.
Here on left is picture of all six possible flavors of quarks. (There can also be antiflavors). Most of matter in universe is made up by up and down quarks. For example neutrons and protons.
Force carrier for weak interaction is w+ boson w- boson or z0 boson.

I was talking about decay so I will show you how beta decay is made by weak interaction.

There is proton with two up quarks and one down quark. It wants to change to neutron because that particle in which this proton is is not stable.
When proton touches neutrino which is carrying w+ boson, boson will move to proton and change one up quark to down quark which makes up neutron. Neutrino will lose positive charge of boson which means it will turn to electron which makes up beta decay!

For summary I would say that weak interaction is responsible for changing of quarks flavor which is many atributes of quarks.

Well that was quite short but that is probably all.
Dragallur
PS. here are links to previous episodes of four fundamental forces:
https://dragallur.wordpress.com/2015/03/20/1-four-fundamental-forces-prologue/
https://dragallur.wordpress.com/2015/03/21/2-four-fundamental-forces-gravitation/
https://dragallur.wordpress.com/2015/03/24/3-four-fundamental-forces-electromagnetism/

# 3) Four fundamental forces: Electromagnetism

Hi guys,
It is made up two forces which we are thinking like extremely different ones.

First I will talk about electro static force.
Well, It is quite easy. When you have two objects and one wants to give electron while the other would like to take some electrons and you will make them touch each other electrons will be jumping there creating one object negatively charged and second one positively charged. (F.g. when you pull your christmas sweather on you, in dark you can probably see little lightings and feel those small shocks.) It is the same wiith battery, one side wants to have electrons so when it is charged it does not have them while second one has lot of electrons but it doesn´t need them so through some wire this difference will be slowly going to equalize by flow of electrons.

Magnetism also works with electrons and that is why these forces could be connected to electromagnetism. Magnet is made up by some special material in which atoms are turning by their pluses and minuses. So in every magnet there are millions of magnets. It does not matter if you make it smaller there will always appear new south and north pole which is made by this turning of atoms.
+  -+  –
+  –
+  –
+  –
Here on right would be south pole (+) and on left would be north pole. It it would be really light (not heavy) and it could easily turn it would be kind of compass.

At last if teacher told you that others things that are not created by Fe,Co,Ni cannot interact with this force they are wrong because you can actually find videos of levitating strawberries because of extremely strong electromagnetic field.
There is also very special attribute of electromagnetism, if you have wire without elctricity and magnet somehow rotating around you can create electricity.
That is way to create elctricity for your house. For example water flowing rotating turbine and magnets around wire is way to get energy. Or by wind rotating turbine or hot H2O flowing in reactor.

Dragallur

# 2) Four fundamental forces: Gravitation

Gravity or gravitation is one of four fundamental forces in the universe. It is also the weakest one as I said in the last post. Unlike other forces it works on much bigger distances. And it only pushes things together.
Imagine having a planet like Earth. It has poles. South pole and north pole. We can see that Earth gravity is pretty strong, it holds us here. So if electromagnetic force is 10^40(something like that) stronger, shouldn´t be electromagnetic field of earth insanely strong? No because electromagnetism works with +(plus) and -(minus) and they will cancel out (almost). Strong and weak interaction are working only on short distances so when you are forming galaxy or star you will work only with gravity.

There are two ways of imagining gravity. (Actually there are more but those are basic)
1) Newton´s way
It says something like this: Every particle in universe attracts all other particles in universe by force which is higher when mass of particles is bigger and is lower when particles are far away each other. Its equation is F=G*(m1*m2)/r
F is force of gravity
G is gravity constant (you can find it on wikipedia)
m1,m2 are masses of your objects
r is distance of objects
2)Einstein´s way

Spacetime is bended by all particles with mass. And it works with all particles even those which are massless, like photons.
Newton´s way does not actually explain some things like orbital of Mars (so it is kind of broken).
On the left is picture of spacetime. You can also imagine your bed which is probably very soft and when you push your matress it goes down. At that point your fist is actually kind of planet, star or black hole and it atracts other stuff around. If you take a ball lay it next to your hand it will go down to center of that hole you created.
I have found awesome video on gravity so here is link: https://www.youtube.com/watch?v=MTY1Kje0yLg
You will see that all forces have some force carrier. Gravitational carrier is massless particle called graviton. It is theoretical, which means it was not detected. Scientists even think that it cannot be detected, but we can see what it does: Gravity!

Dragallur

# 1) Four fundamental forces: Prologue

Hi again, for fourth time!
I am subscribing some science channels on youtube. SciShow, VSauce, MinutePhysics or Veritasium. They are all awesome and I would like to recommend them to you. Plus I would like to thank to them because I learned a lot of stuff from them.
Anyway, few weeks ago I watched serie from SciShow. There were videos about fundamental forces. Because I would like to write about what i learned on this blog it inspired me to do something similar and try to explain what are those fundamental forces.

This post will only be about what are they together and then I want to talk about them one by one.

So there are four fundamental forces. You could also say basic forces. They have some similarities and all of them have force carriers.
First one is gravitation. It is probably the most strangest one. Gravitation is strange because it only pulls things together. Gravitation is atribute of every particle with mass. It is also crazy weak. Electromagnetic pull between two particles with different charge is 10^42 stronger than gravitation between two particles!

Next one is electromagnetism. It occurs between two objects with some charge. On the beginning of 19th century electromagnetism was created by putting together electric force and magnetic force.

Another is weak interaction. It is (for me) far more complicated i think. It affects very small stuff like quarks. It is also responsible for beta decay. Its carrier is photon.

Last one, also very complicated is strong interaction. Strong interaction is very strong. It is that strong that it can create new massive particles! Again it works on small scale and its force carrier is gluon.

Well that was short overview for fundamental forces. I will talk about them later, one by one.
Thank you for your likes and comments, as I said before, I really appreciate them!
Dragallur