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B Is my summary of these subjects correct?

  1. Dec 3, 2016 #1
    I plan on making some videos talking about certain subjects in physics and so I have been watching some videos. I have formulated my own interpretation and understanding of these subjects in this summary.
    And I was wondering if any of you could take a look and correct me if I am wrong so that I have the good understanding of the subjects.

    I dont want to go and spread false information.

    Well here is my summary, manu different topics are discussed:

    General relativity.

    You move through space and time and if you drop an apple then something pushes the apple down. This is called gravity. What actually happens though is that space pushes the apple down to the earth because the earth's energy bends space-time. The path of the apple is now directed into the earth. Everything that wants to orbit the earth needs to be moving before coming into orbit. This is always the case because it wouldn’t get into earth’s orbit if it wasn’t moving. The earth also has a sideways motion that prevents it from going into the sun. It got this motion from the formation and collisions of asteroids that formed the earth.

    -Space-time tells matter how to move and matter tells space time how to curve. The universe has an escape velocity just like the earth has a velocity at which you can escape to space. Escape velocity is basically kinetic energy being transferred into potential energy by the "gravitational" pull. If the sum of these two for the universe is more than 0 than the universe will expand forever. If it less than it will collapse eventually. After some calculations it is now known that the universe will expand forever. The universe just isn’t dense enough to collapse back on itself. It doesn’t have enough mass(energy).

    -Every observer has the same space-time path but they can change the axis so that it looks like that object is moving instead of being inertial. The observer in the object sees itself as inertial and will change the axis of space-time so that it looks to be inertial.

    -Another thing that curves space time is pressure.

    QUANTUM

    Quantum Field Theory

    The elementary articles like electrons are excitations in fields. These fields fill our universe. And these fields are everywhere. A vibration in a field is the particle. A vibration in the electron field is an Electron. These vibrations in fields interact with each other transferring energy momentum and so on between particles and fields.

    Higgs Field

    It gives an electron hypercharge and takes it away in a very small amount of time. This causes the electron to flip spinning directions constantly. And this means it experiences time and if it experiences time it must have mass. Basically it gives a particle inertia. It gives it resistance to acceleration.

    QUANTUM MECHANICS

    Certain properties of an object must be fundamentally uncertain. They don’t hold any values but must be described as a distribution of possible states of "being". Each state has a certain possibility of being true until the object is observed. Until a quantum object interacts with something, all possible states are just as real as each other. But they don’t always have the same likelihood of being true. The likelihood is rather distributed across different probabilities for each quantum property. That distribution and the way it changes over time is coded in the wave function of that object. If you collapse a wave function by for example interacting with a particle you will know its properties.

    DE BROGLIE WAVELENGTH

    Any material object can be seen as a matter wave. It can be seen as a position probability. And this has a wave length. This is called the De Broglie Wavelength. This wavelength illustrates how certain the position of an object is. A large wavelength means a highly uncertain position and thus a small wavelength means a well-defined position. But every object still has a chance to be somewhere completely different no matter how small the wavelength is. It is true for subatomic particles and also kind of works for anything.

    There is a really small chance that I am actually on the moon right now. But if you observe me you will collapse my wave function and see that I am actually not on the moon.

    De Broglie Wavelength of an object depends on its momentum. The more momentum the smaller the wavelength. And so because we humans are made of very many particles with momentum our position is really certain. Even smaller than the Planck constant so we can’t be in another position.

    QUANTUM ENTANGLEMENT

    Two particles interact and influence each other so that their properties are connected. This particle pair must be described in a single combined wave function with all the possible combination of states for both particles. This particle pair is called an entangled pair. If the Copenhagen interpretation is true than an observation of one particle would change the properties of that other particle instantaneous. And would suggest that one particle could influence the other particle instantly over an infinite distance and even back in time. It seems like this is true but this doesn’t break causality as we can’t manipulate the information being sent between these two quantum particles.

    THE PLANCK CONSTANT

    This constant is a measuring tool for energies at quantum levels. This constant was needed to let certain observations be explained. It was thought that the smaller the wavelength of a photon the more spectral energy density. But this would make it infinitely go up. And say that a star would emit a lot of gamma rays and less visible light. Which didn’t match observations. So Planck invented this complicated constant to make the equation match the observation.

    COPENHAGEN INTERPRETATION

    An experiment seems to suggest that in between creation and detection of for example a photon. It is unknown where it will be and where it is and that it is actually not something physical. In between, it is rather just a bunch of possible locations and only at the moment of being observed it is randomly decided where it will be at and what its path has been. In this interpretation it is suggested that in this space a particle is only its wave function and so it is just a wave of possible locations and paths. Quantum mechanics predicts this by describing each particles journey in between creation and detection as a superposition of all possible trajectories. So the particle takes all possible paths at the same time. And that these possible paths can interact with each other if they are split by a wall with 2 holes and make one position more possible than another when detected. And so most particles will end up where it is most likely to be at due to the interaction of the possible paths.

    This interpretation suggests that at the moment of wave function collapse there is a transition between wave and particle. This is the transition between the quantum and classical realms.

    If we try to see if it is indeed a wave or a particle it seems like the photons communicate to each other that they have to have been behaving like a particle all along. They seem to even be capable of doing so after one photon has already been observed. But if you observe the behaviour of the photon it seems like they change their way of behaviour to acting like normal particles. So they seem to be able to erase their previous behaviour. So we can't prove if they are indeed waves in between creation and detection. And then if we make these observations of behaviour random again they behave like waves again. It is like they don’t want us to know.

    PILOTWAVE

    Its similar to Copenhagen but it says that the wave pushes the actual particle along and that there are a few uncertain properties to the wave function. If you measure the wave and particle, then these properties can drastically change its path as seen in the experiment. This interpretation is very simple in that the wave is now something physical.

    Many worlds interpretation

    In this interpretation there are infinite timelines in which all the possible positions of things actually happen. And all of these timelines are equally probable. But some of them look very much a like and these are the ones most common. We just live in one of these timelines. This would mean that at any interaction between 2 particles an infinite amount of new timelines would be created. So there would be an infinite amount of alternate timelines. In the case of the Copenhagen interpretation these possible timelines combine into the observer’s timeline. But in this interpretation every possible timeline stays separate and creates a whole new set of possible timelines.



    SPACE TRAVEL

    We are trapped in our own space bubble because all the other bubbles are moving away faster than the speed of light.

    A warp drive is possible if you can compress space-time in front of a spaceship and expand it behind a space ship this way the ship is moved by space-time, faster than light ,but the crew wont actually feel acceleration. This doesn’t break relativity because space-time can move faster than the speed of light.

    Aliens

    We are only 2% different from chimps and we can do so much in comparison to them. So if aliens are at least 2% different in a positive way from us then they would be able to do so much and see us as chimps in comparison to them. Maybe that "big" difference between us and chimps isn’t that big at all. But rather as small as the 2% genetic difference suggests. So aliens might just not be interested in us if they do see us. We don’t go talking to worms so why would they. If they were to interact with us they could enslave the human race without us even knowing. Their toddlers could be memorizing quantum mechanics something the smartest humans can’t even do.

    Another thing to realise is that if you want to communicate with another species they have to be able to receive or perceive our message. If aliens sent us a radio wave 200 years ago. We wouldn’t have noticed and they would have thought there is no life here. Maybe this has already happened and our planet has just been marked to have no intelligent life. Aliens could also be so advanced that they don’t recognize our primitive communication methods. There could just be a really small time gap in which you could talk to another civilisation before it becomes to intelligent or destroys itself.

    We are lucky that we can even see the distant galaxies. Future civilisations will think that their space bubble consisting of their galaxy and one that is still gravitationally bound to it, is the only thing there is. Because the other galaxies will have gone so far apart that you won’t see them anymore.



    MAGNETS

    Magnetic fields are made when electricity moves around. Transferring the electric field into a magnetic field.

    Well why does a magnets have a field when it doesn’t move?

    Magnetism is created by the electrons in atoms which move around. If you have a full electron shell, then the magnetism of those pairs will cancel each other out that is why atoms with almost full shells aren’t very magnetic. But if the shell is half full it won’t cancel out and so the atom will be magnetic. But magnetic atoms don’t mean that the solid state is magnetic too. There are different ways magnetic atoms can align.

    Anti-ferromagnetic

    One way is to alternate between up and down and this will in turn cancel out so that the solid isn’t magnetic.

    Ferromagnetic

    This way the atoms all align the same side up and down so that they don’t cancel out this will make it magnetic. Iron or Fe is even called after Ferro so it is really magnetic.

    What a solid does just depends on what takes the least amount of energy to accomplish. So if you don’t need much energy to go into anti ferromagnetism then the solid will do that. An example of this is chromium. But if an iron block has 5 different parts that all point in a different direction then it will still not be magnetic. You can influence this by putting magnets next to and let one part take over the others.



    PHOTONS

    SPEED OF LIGHT.

    The speed of light is really the speed at which two points can influence each other. It is the speed of causality.

    A photon experiences its entire life in one moment. So if you were to be able to travel at the speed of light you would see your whole life in one moment.

    E =(mc2)2 + pc2 but you can ignore pc2 if the object isn’t "moving".

    A photon is emitted when an excited electron falls down to a lower energy level. The energy lost by the electron goes into the photon in a specific wavelength. That is why something really hot starts to glow. Photons have different wavelengths the bigger the wavelength the less energy it contains.

    The reason for an electron to go into a higher energy level is to absorb the energy being put into it. It goes higher so its gravitational energy increases and it absorbs the energy from for example a photon. An electron only goes higher when the exact amount of required energy is provided. If it is too much or not enough it won’t go higher. There are no states in between two energy levels.

    An electron only goes up an energy level if it is provided exactly enough energy to go up. If it’s more or less it won’t go up

    Lasers

    In a laser atoms are excited and electrons jump up an energy level. If they go back down they emit the energy in the form of a proton. If there is one proton. It likes to have otger photons with it. And so other atoms start emitting photons. The photons want to be together even before they aremade. These are all concentrated in between reflective surfaces. And an opening will let out a laser.

    Heat

    Infrared (photon with high wavelength) from sunlight has a longer wavelength and thus resonates well with atoms. This sets the atoms into motion.

    It is also so that atoms always vibrate and when they vibrate as much as the amount of electronical energy absorbed they can make a quantum transition between electronically excited to vibrationally excited.

    Stars

    You can see what a star is made of by looking at its light. The elements that the star is made of will leave a certain dark spot in between the colours of the light these are the colours they absorb and by categorizing them you can see what element absorbs what light. This happens because every atom has different electron energy levels. So every atom's electrons will need a different type of photon with that exact energy to jump higher. And because of this absorption by these atoms inside the star, they leave dips in the spectrum where these type of photons where absorbed. And so we can categorize what atoms absorb which photons and calculate the concentration of that atom in a star.

    This way you can also see what gas clouds are mad of. They absorb certain photons but then later on randomly disperse them.

    Extra:

    As space is expanding it stretches out the light that is traveling through it. It increases the wavelengths of light. Resulting in red shift.

    You can calculate how far away a galaxy is by viewing how faint it is. You will need to compare that to a standard candle. Something of which the full lightness is known.

    Quantum tunnelling seems to be instantaneous and be faster than the speed of light. But any photon could arrive a bit faster than another one due to its wave packet. Adding a "wall" only makes it so that only those that do arrive a bit faster actually arrive.



    RADIATION

    Radiation is when a nucleus of an atom emits energy in the form of protons and neutrons. Every atom emits a bit of radiation. Normal small atoms are held together fine by the strong nuclear force. The nucleus of an atom wants to go apart because it is all positively charged. But the strong nuclear force holds it together.

    There is a perfect ration between neutrons and protons. If an atom isn’t like that then it gives of neutrons and protons to get back to that ratio. So it emits radiation. The smaller atoms don’t have many protons or neutrons. But uranium has a lot of them so it has way more radiation. Because it wants to go apart way more. There are different forms of decay as listed below.


    Alpha decay

    An alpha particle is made of 2 protons and 2 neutrons. This particle can be a part of a heavier nuclei. In this nuclei it can move around but it can’t escape due to the nuclear force holding it there like a wall. But the position isn’t well defined. The wave packet (possible locations of that particle) is usually reflected back when it hits the inside of the nucleus. But that packet doesn’t end at the wall of the nucleus. It goes on through the wall, but the chance of it being there drops of drastically. But it never reaches zero. There is a very small chance that the alpha particle doesn’t bounce back but actually appears outside of the nucleus. And it will be in that unlikely probability space outside the nucleus. This is called quantum tunnelling. This alpha particle escaping a nucleus is a very important mechanism for radioactive decay. But it can happen with other particles as well. It also goes in both ways. Protons, electrons, neutrons and alpha particles can also quantum tunnel into nuclei.

    Alpha decay is basically giving of helium atoms.

    Beta decay

    This is negatively charged and is an electron going away. This happens when a neutron becomes a proton so it gives of an electron. This can happen in fusion for example.


    Gamma radiation

    This is made when the nucleotides (Protons and neutrons) in the nucleus start to wiggle around because of the nuclear force, they want to go back to a not excited state. And this wiggling and going back to their ground state gives of gamma radiation. So the bigger the atom the more gamma radiation. Gamma rays are photons with very high energy.

    Cause of cancer

    Gamma rays and radiation give of energy to electrons when passing through solids like the skin. This can screw up bonds between molecules for example in DNA. If both strands are broken it can be repaired but these repairs may miss a nucleotide and thus change the DNA sequence and cause mutation and or cancer. This can also result in cell death. They give of energy to atoms resulting in electrons going in higher orbit and electrons being given of. But in this case electrons in a lower orbit can also be given of.

    Fission

    This is the splitting of heavy nuclei into smaller more stable ones. As said before nuclei have a specific ratio which they want to achieve (Iron is the best one). This splitting can occur when you shoot a neutron onto a uranium nucleus, this will make the nucleus even more unstable and it will split into other atoms which are more stable and thereby releasing the previously stored strong nuclear binding force in the form of kinetic energy. This is what happens in nuclear power plants. The one neutron lets the uranium split into 2 other atoms and releases 3 other neutrons these can hit another 3 uranium nuclei. And this will create a chain reaction. The energy released is in kinetic energy this is used to make steam out of water and let turbines spin.


    Fusion

    Here small nuclei are combined under high pressure and heat, the sun for example has a core of 15 million kelvin (At least 10 million kelvin is needed to fuse hydrogen). Because of the huge amount of temperature (10 million kelvin or more), the electrons go to such a high energy state that they are not bound to the nucleus anymore. The higher the energy level the less banded an electron is to its nucleus. This makes it possible for protons and electrons to move around freely which is the definition of plasma. When 2 protons do collide, they overcome the electromagnetic repulsion and get close enough for nuclear force to bond them together. One proton becomes a neutron releasing a positron. If this positron hits an electron they annihilate and create 2 photons that transport the energy of the positron and electron. That’s why fusion creates energy.

    So 2 hydrogen atoms collide and form a hydrogen atom with more mass called deuterium. Deuterium collides with hydrogen and forms helium 3 (made of 2 protons and 1 neutron) all these reactions give of heat and photons (as mentioned above). Then 2 helium 3 atoms collide and form a helium 4 atom and 2 hydrogen atoms plus some more energy. Because the small nuclei have a much bigger binding force difference between two different atoms a lot of energy is produced. With fusion this difference isn’t so big. Because it only happens at very high speeds (Temperature) it gets too warm to control. That’s why we can now only use it for bombs.

    Here is some extra info on why energy is released:

    It releases energy because two hydrogen atoms have more potential energy then a helium atom. So the excess energy is emitted in heat and photons (Different wave lengths). Hydrogen wants to form this bond because this bond requires less energy than it does when they stay a part. Helium has more binding energy then hydrogen. Binding energy is the energy needed to separate a nucleus. So less energy is needed to hold them together. If 4 protons are split, they get more potential energy which is why they are heavier when they are a part. And when they are combined they move towards each other losing potential energy and putting it into photons (first positrons and electrons).



    CLEAN ENERGY

    Cpv’s are concentrated photovoltaic cells using mirrors to focus a bigger area of light onto smaller parts of solar panels giving way more energy for your money than normal solar panels.

    Solar panels are made of silicone. This silicon is distributed in 2 layers. One layer has too many electrons because it is mixed with a molecule that has 5 electrons like phosphor. The other layer gets mixed with boor which has only 3 electrons so it has spots open for electrons. On the junction of the two layers the electrons fill up the holes. Now phosphor is positively charged because it has 1 less electron. And the boor is negatively charged because it has one more electron. When a photon hits an electron it can jumps out of the orbit and is attracted to the positive charge (1st layer) which is where the free electrons are all at. The open spot can move because of different Lewis structures allowing the bonds to move. The open spot moves down to the negative charge (2nd layer) and finds the other open spots. The electrons can’t make it to the open spots because the negatively charged boor is repelling them. So if you connect a wire from one layer to the second layer they will flow through it to get to the open spots. If you put your devices in between then they will get the kinetic energy converted from the photon impact. When the electron is used it returns and fills that a spot.

    Electrons always have kinetic energy, but when hit by a photon they speed up and can escape the proton. They move along a wire and create an electric field that can power devices. When they arrive back they go orbit an atom again and so they lost some kinetic energy because they don’t have enough to escape anymore.


    Turbines let electromagnets move making a moving magnetic field that forces electrons to move in a certain direction.

    BATTERIES

    These work based on oxidation and reduction between two substances. One material oxidizes and sends electrons to the other substance which is reduced creating another material. If you plug in something in between then it will lose the electric field. There is a positive and negative side in the battery. If you discharge (use energy), then the electrons move from the negative side to the positive side to reduce the positive ions. If you recharge they go the opposite way (against the flow) that is why energy is needed to recharge.
     
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