the standard model atomic structure,and the bing banganti-matter,winos,zinos,

The Standard Model

Atomic Structure, and the Bing BangAnti-Matter,Winos, Zinos,

The Standard Model is the current theory behind Quantum Mechanics:

• Every prediction ever made by the Standard Model has come true - except one, which has yet to be tested.• It has explained with extreme precision how most particles smaller than atoms behave and react.• Although extremely successful, it is on the verge of being surpassed by other theories.• It fails to explain gravity and why things behave the way they do on large scales.• It fails to present a “unified field theory” - a theory that shows that everything and every force are simply different expressions of the same thing.

The Standard Model:Fundamentals


• There are 4 forces that govern interaction between particles.• There are 18 particles that make up all of matter.• Every particle has an anti-particle.• If a particle and its anti-particle come into contact, they will explode in a violent burst of energy.• Most neutral particles are their own anti-particle.


The 18 particles:• The 18 particles are divided into two groups:• Particles that make up matter and physical objects are called Fermions.• Particles that carry one of the 4 forces are called Bosons.• There are 12 Fermions and 6 Bosons.

Fermions


The 18 particles:

QuarksQ

6 Quarks

Leptons

E

Electron

E

3 Neutrinos

M

Muon

T

Tau Particle

Bosons

G

Gluons

P

Photons

G

Graviton

M T H

Higgs Bosons

W Z

W & Z Bosons

S The Strong Nuclear Force

W The Weak Nuclear Force


The different forces:

E The Electromagnetic Force

G Gravity

Bonds

From Hydrogen (and even to Van der Waals)to Metallic

There are two types of “bonds”:

• “True” bonds - those between atoms and molecules to make larger molecules

• And “dipole-dipole” interactions - interactions between molecules (like a Gecko’s feet and a wall its climbing on)

Atomic Structure

Atomic Structure

H+

-

O

Atomic Structure

• Electrons come in “shells”.• The first shell can only hold 2 electrons.• The second can hold up to 8 electrons.• The third can hold up to 18.• There are 7 shells that currently exist.• More are possible.

Atomic Structure

• Electron shells are in turn made up of “orbitals”.• Each orbital can only hold 2 electrons (one having “spin up”, the other “spin down”).• The first shell only has 1 orbital.• The second has 4.• The third has 9, and so on.

Atomic Structure

• Electrons can theoretically appear anywhere in the Universe.• They usually spend their time around the atom within certain areas or zones.• Each area forms an orbital.• Electrons are one of the fundamental Fermions.

Atomic Structure:In Depth


The Nucleus


• The nucleus of an atom is extremely small and dense.• It makes up a tiny fraction of the whole atom: it’s diameter is about 0.01% of the diameter of the whole atom.• It makes up, however, 99.95% of the atom’s mass (or weight).• It is incredibly dense: if a deuterium atom’s nucleus (1 proton and 1 neutron) were the size of a bouillon cube (1 cm3), it would weigh 6.6 million tons.


• The rest of the atom’s volume is empty space in which electrons are able to move about in.


• Every element’s (oxygen, aluminum, gold, etc.) atoms have the same number of protons.• This defines how the atom’s electrons will “orbit” around the nucleus and which shells and orbitals are filled up.• This gives each element its distinct properties.• The difference between aluminum and oxygen is the number of protons the atoms contain.


Oxygen Flourine Sodium8 protons 9 protons 11 protons


• Neutrons serve to help hold the protons in the nucleus together.• Because protons are all positively charged, they would normally repel.• Neutrons put space between the protons and give them something to stick to other than each-other.• The Strong Nuclear Force overcomes the Electromagnetic Force and helps to hold the nucleus together.


• The same element can have different numbers of neutrons. These are called isotopes.• Hydrogen-2 is an isotope of hydrogen that has 1 neutron and 1 proton.• Hydrogen-3 is an isotope of hydrogen that has 2 neutrons and 1 proton.• Some isotopes are radioactive, while others are stable• Too few or too many neutrons can make an atom unstable.


• Protons and neutrons are made up of smaller particles known as quarks. • Three quarks makes up a proton or neutron.• Whether the particle is a neutron or proton depends on what quarks make up the particle.• The Strong Force also holds the quarks together to form larger particles.


• There are six “flavors” of quarks.• Each quark can come in different “colors”.• Quarks can only combine into “colorless” particles (3 being red, green, and blue or 2, one being red, the other “anti-red”)• A proton and neutron are three quarks, one being red, another green, and the other blue.


• Quarks, like all particles, have anti-particles - anti-quarks.• Some particles are a combination of only two quarks, one anti-quark and one quark.• Whether a quark is red, green, or blue, or an anti-quark is anti-red, anti-green, or anti-blue depends on the strong force “charge” that it is carrying.• Quarks make up 6 of the fundamental Fermions.


U

Up Quarks

The different “flavors” of quarks:

D

Down Quarks

C

Charm Quarks

S

Strange Quarks

T

Top Quarks

B

Bottom Quarks


• Protons and neutrons are made up of a combination of 3 Up and Down quarks.• A proton is made up of 2 up quarks and 1 down quark.• A neutron is made up of 2 down quarks and 1 up quark.


D

U UU

D D

Proton Neutron

+2/3 +2/3

-1/3

-1/3 -1/3

+2/3


D

U UU

D D

Proton Neutron


D

U U U

D D

Neutron


Electrons


• Electrons make up only 0.05% of the total atom’s mass.• Unlike protons and neutrons, electrons are not made up of any smaller particles. (Except in string theory)• Electrons participate in chemical bonding - especially those in the outermost shell of an atom.• These electrons are known as valence electrons.


• Electrons are organized into shells, which are in turn made up of “orbitals”.• Each orbital can only hold 2 electrons.• Orbitals are regions or clouds where there is at least a 90% chance of finding an electron at any given point in time.


• The first shell can only hold two electrons.• This is because it only has one orbital, known as the “1s” orbital.• It is shaped like a sphere.


The “1s” orbital


• The second shell can hold up to eight electrons.• This is because it has four orbitals.• The first is known as the “2s” orbital.• It is shaped like a sphere.• The next three are grouped together and are known as the “2p” orbitals.• They are shaped sort of like two jelly beans side by side.


The “2p” orbitals


• The third shell can hold up to eighteen electrons.• This is because it has nine orbitals.• The first is known as the “3s” orbital.• It is shaped like a sphere.• The next three are grouped together and are known as the “3p” orbitals.• They are shaped sort of like two jelly beans side by side.


• The next five are grouped together and are known as the “3d” orbitals.• Four of of them are shaped like four pieces of candy-corn arranged with their cones facing each other.• The fifth looks like two pieces of candy-corn facing the middle of a donut.


The “3p” orbitals


The “3d” orbitals


• The fourth shell can hold up to thirty-two electrons.• This is because it has sixteen orbitals.• The first is known as the “4s” orbital.•The next three are grouped together and are known as the “4p” orbitals.• The next five are grouped together and are known as the “4d” orbitals.


• The last seven are known as the “4f” orbitals.• Four of them are shaped like six pieces of candy-corn/jelly beans that are facing each other.• Two of them are shaped like eight pieces of candy-corn that are facing each other.• The last one is shaped like two pieces of candy-corn facing towards the middle of two donuts.


The “4f” orbitals

There are two things atoms want:• They want to be electrically neutral.• They also want their outer-most shell to have the maximum number of electrons.

Covalent Bonds

Covalent Bonds

• Are the most common type of bond• One of the strongest types of bonds• Is the familiar ball-and-stick model of molecules• Is a “true” bond• Atoms bond by sharing electrons

Covalent Bonds

HH

OO

HH

H2O

Covalent Bonds

Ionic Bonds

Ionic Bonds

• Another common type of bond• An example is salt: chlorine and sodium ionically bonded together• Is a “true” bond• Atoms bond by donating and receiving electrons

Ionic Bonds

Cl

Na

Ionic Bonds

+

-

Na

Cl

Ionic Bonds

+

-

4Na+Cl-

+

-

Na

ClNaCl Cl

NaNa

Na ClCl

Metallic Bonds

Metallic Bonds

• Are the strongest type of bond• The bond that forms metal• A “true” bond• Forms a malleable, ductile, strong, conductive solid• An example is any metal: steel, aluminum, iron, etc.• Bonds by all atoms sharing their outer electrons

Metallic Bonds

Fe

Metallic Bonds

Metallic Bonds

FeFe

Fe

FeFe

FeFe

Fe

+-

Fe

Van der Waals Force

Van der Waals Force

• Van der Waals Force are any “dipole-dipole” interactions except Hydrogen Bonds• Can form between any molecules or atoms• Are very, very weak

Van der Waals Force

OO

Van der Waals Force

Hydrogen Bonds

Hydrogen Bonds

• Are the strongest form of “dipole-dipole” interactions• They form between water molecules• Without them, biological life would not exist, nor would liquid water• It is what gives water its very strange properties• Are partially covalent

Hydrogen Bonds

HH

O

• Water is made up of two Hydrogen atoms (the periwinkle) and one Oxygen atom (the red).• Water is an extremely small, reactive molecule.• It is smaller - and lighter - than either an Oxygen molecule or a Nitrogen molecule.• Without hydrogen bonds, liquid water would not exist on Earth.

Hydrogen Bonds

HH

O

Atomic Weight: 14-16 Atomic Weight: 24-32

Water Molecular Oxygen

OO

Hydrogen Bonds

HH

O

+

-

+

Hydrogen Bonds

HH

O

HH

O

HH

O

Hydrogen Bonds

Hydrogen Bonds

HH

O

HH

O

HH

O

HH

O

HH

O

HH

O

HH

O

HH

O

HH

OH

Hydrogen Bonds

• Hydrogen bonds cause water molecules to form a dynamic network in a liquid.• The network is constantly changing as bonds break and form.• The stretching and pulling on the water molecules’ hydrogen atoms causes water to vibrate at certain frequencies.• These vibrations absorb radiation, such as microwave or infrared radiation.

Hydrogen Bonds

HH

O

• Hydrogen bonds cause water molecules to be very unstable.• In less then 1 millisecond, at least one of a water molecule’s hydrogen atoms will break off and join another molecule.• The remaining OH molecule will quickly bond to another free hydrogen atom that has been lost by another water molecule.

Hydrogen Bonds

How Water Deprotonates

(See Flash Movie)

Hydrogen Bonds

• Because of the angle of hydrogen bonds, ice is less dense than liquid water. This allows life to continue in frozen lakes and streams.• Because of water’s “sticky” qualities, it has high surface-tension, allowing water bugs to “stand” on the surface.• Because water is polar, it is able to dissolve a vast number of molecules.• It is also crucial to almost all organic chemical reactions because of its polarity and volatility.

Hydrogen Bonds

• Hydrogen bonds also play a part in other molecules.• They hold together our two DNA strands.• They play a major role in “folding” proteins up into the correct shape.

H

C

NN C

C CN

C

N

H

H

NH

H

C

C C

NC

C NH

O

HH

H

+

+

-

-

AdenineThymine

C

NN C

C CN

C

N

H

H

NC

C NH

Hydrogen Bonds

H

NN

H

H

C

C C

O

HH

H

+

+

-

-

GuanineCytosine

C

NN C

C CN

C

N

H

H

NC

C NH

Hydrogen Bonds

H

NN

H

H

C

C C

O

HH

H

C

NN C

C CN

C

N

H

N

H

H

O

H

HC C

NC

C N

H

O

N

H

H

+ -

Hydrogen Bonds

How Proteins Fold

(See Flash Movie)

Hydrogen Bonds

How Water Dissolves Salt

(See Flash Movie)

The Standard Model:How Particles Interact


• Particles interact by exchanging bosons.• Some particles are only affected by certain forces, and thus, certain bosons.• Neutrinos are not affected by the Strong or Electromagnetic Forces.• Bosons carry specific amounts of energy. According to the Standard Model, energy can’t be exchanged in amounts less than one boson.


Photons and the Electromagnetic Force


• Photons are the carrier particles for the Electromagnetic Force.• They are what you see as light.• They are what cooks your food in the microwave.• What radio, cell phone, and TV signals are transmitted with.• What powers your house, your computer, your automatic garage door opener.• And are what let doctors see your bones (X-Rays).


• The Electromagnetic Force is responsible for magnetic fields, electricity, why charged particles repel or attract, why atoms form molecules, friction, light, and much of what we see and experience at the macroscopic level.


• All charged particles (e.g. protons, electrons, W bosons) interact with the Electromagnetic Force.• All charged particles are surrounded by both a magnetic field and an electric field.• This forms the electromagnetic field.


• When particles move, they cause ripples, or waves, in their electromagnetic fields.• These waves are photons, and what we see as light.• For example, as electrons move (wiggle) in the metal filament in a light bulb, they bump into the metal atoms, causing them to vibrate faster and heat up to ~4,000º F.• This causes faster ripples and the release higher frequency waves - photons of visible light.


• This is how particles repel or attract to one another - via photons. • One particle won’t be attracted to or repelled by another particle until one particle’s photons have reached the other particle.• They won’t “see” each other until photons have been exchanged.• At short distances, this is basically instantaneous, but at long distances, it has noticeable effects


How Protons and Electrons Interact

(See Flash Movie)


• The Electromagnetic Force has an infinite range.• That means that every charged particle in the whole Universe is feeling the effects of every other charged particle, albeit weakly.


Gluons and the Strong Force


• Gluons are the carrier particles for the Strong Force.• The Strong Force is the most powerful of the four forces.• They are what hold quarks, protons, neutrons, baryons, and mesons together (like “glue”).• They are what allows atoms’ nuclei to stay together.• The Strong Force only affects quarks and particles made up of quarks (e.g. protons, neutrons, mesons).

U

D

U U

D


• We generally don’t feel the effects of the Strong Force (i.e. my protons and neutrons aren’t being attracted the wall’s, whereby I would be stuck to the wall) because it has a very short range.• One quark can only feel the effects of another one that is close by.

U

D

U U

D


• Quarks exchange gluons that carry “color charge” (which can be (anti-)red, (anti-)green, or (anti-)blue.• Like “colors” repel, opposites attract.• Most of a proton’s or neutron’s mass comes from the attractive energy between the three quarks, rather than from the quarks themselves.

U

D

U U

D


D

U U


• The Strong Force becomes more powerful the farther away the particles are, until the particles are outside the range of each other, whereby the Strong Force becomes almost negligible.• Because of this, quarks have never been seen alone, only in pairs or groups of three.

D

U U

U

D


How Quarks Separate

(See Flash Movie)


• The Strong Force is also what holds protons and neutrons together in a nucleus.• It is know as residual Strong Force, because it arises out of the bonding between the individual quarks.

D

U U

U

D

D

U U

D

U U

U

D

U U

U

D D


D

U U

D

U U

U

D D

U

D D

U

D D

D

U U

D

U UU

D D


W and Z Bosons and the Weak Force


• The Weak Force is mediated by two different bosons, named “W” and “Z”.• The Weak Force is a force that allows particles to change into each other.• For instance, a proton may turn into a neutron and vise versa.• It is the weakest of the fundamental forces, except for gravity.• It affects only quarks and leptons.

W+

W-

Z


• It is responsible for most radiation, the sun’s ability to give off heat and light (and thus sustain life on Earth), and the creation of elements heavier then iron (like copper, zinc, silver, iodine, etc.), and so necessary for the creation of planets.• The W and Z bosons are extremely massive particles at 80 GeV and 90 GeV respectively (iron atoms are lighter).• It has an extremely short range - less than 0.1% of the diameter of a proton.

W+

W-

Z


• The W boson is negatively charged. • Its antiparticle is positively charged.• The Z boson is neutral and is its own antiparticle.• Only interactions involving the W boson actually cause particles to change.

W+

W-

Z


Weak Interaction

(See Flash Movie)


How the Sun Glows

(See Flash Movie)


How Heavy Elements Form

(See Flash Movie)


Gravitons and Gravity

The Standard Model:Wave/Particle Duality


• In the Standard Model all particles, and everything, are both waves and particles at the same time.• Or neither.• They may be something that behaves like a wave some of the time and like a particle other times, but is something entirely different (a “wavicle”?)• If you test for wave-like properties, you will find wave-like properties.


• If you test for particle-like properties, you will find particle-like properties.• Scientists don’t know why. It’s “just the way it is”. They see no point trying to find out why, as the theory works, and that’s what (they think) is important.


• The concept of waves and particles started in the 17th and 18th centuries.• It was centered around a great debate: whether light was made of particles or waves.• Isaac Newton believed light was composed of a stream of particles he called “corpuscles”.• Others believed light was made of waves, much like sound waves.


• At first (because of Newton’s celebrity), people believed in the “corpuscle” theory.• By the end of the 19th century, however, a set of experiments had shown (seemingly) conclusively that light was made of waves.• One of these was Thomas Young’s “two-split” experiment.


Wave Crest

Wave Trough

Wave Length Amplitude


• It was the end of the corpuscle theory.• For the next 100 years, scientists were certain light was a wave.• Advances in the theory of light, electromagetism, and other phenomena made physicists feel pretty good about their theories.


• At the turn of the 20th century, they thought they had the whole world figured out.• The two known forces - electromagnetism and gravity - could be explained incredibly accurately.


• James Maxwell had united Electricity and Magnetism as one force and discovered that light was electromagnetic.• He also developed formulas to explain how electromagnetism would behave.• Isaac Newton had explained the effects of gravity using his own equations.


• Physicists believed they could explain how just about everything worked.• They believed the fundamentals had been discovered, and the following years would be used to simply refine the theories by “another decimal place”.• There were just a couple problems. But they were sure someone would figure it out…


The Ultraviolet Catastrophe


• The ultraviolet catastrophe had to do with what would happen to an ideal black body when heated.• A black body is a theoretical object that does not reflect any light or radiation.• It absorbs all frequencies of light equally, and re-emits all frequencies equally.• An oven is a good analogy.


• An object that would absorb all (or most) frequencies would appear as black to us when not heated.• As an object is heated, its electrons release radiation.• The hotter the object gets, the higher the frequency emitted.• If heated to about 1300° F, a black body will start to emit visible light in the form of red light.• At about 17,500° F, it will reach the blue/violet spectrum.


• Above that, and it will start to emit ultraviolet rays, x-rays, and finally gamma rays with increasing intensity.


• The problem was that the equations at the time predicted a rather odd result: a heated object should be emitting an infinite amount of radiation.• Your chicken, and your house, would promptly explode in a fiery ball of plasma when you turned on your oven if this were true.• They also predicted that ultraviolet rays should also be the most common rays emitted by a heated object.


• They also predicted that as an object heated up, it would simply start glowing blue, rather than starting red and moving up the spectrum. • Neither is true, as your oven will emit very few ultraviolet rays - most come in the infrared spectrum (heat) and lower.• And an oven doesn’t glow blue inside when you turn it on.


• This came about because of the beliefs at the time in how light and atoms were made.• The prevailing theory was that atoms were little hard positively charged balls with electrons attached by something like little tiny springs.• When the electrons were excited, they would wiggle back and forth really fast and create electromagnetic ripples - light or radiation.


Nucleus

Electrons (“Oscillators”)


• Physicists believed that the “oscillators” could emit radiation at any frequency.• They also believed that the frequency of the light made little difference to the amount of energy it had. They believed the energy lied primarily with the intensity of light (the amplitude of the wave).


• Imagine a tsunami hitting every 2 hours. It has a very low frequency, but a very high amplitude.• Compare that too a ripple hitting every 5 seconds - high frequency, low amplitude.• The tsunami is much more powerful, even though it is at a lower frequency.


• Because “oscillators” could emit light at any frequency, and because they believed that any radiation emitted had to be in every possible frequency:• There should be an infinite number of frequencies.• Thus, there should be an infinite amount of energy (all frequencies have to be emitted).


• The problem was solved by a German Scientist named Max Planck in 1900.• It was an “act of desperation” (he had been working on the problem for 6 years).• He wrote that “a theoretical interpretation had to be found at any cost, no matter how high.”


• He assumed - for no theoretical reason, a guess in essence - two things:• First, that light waves cannot exist at any arbitrary frequency. It can only exist at whole integers of some really small value, called Planck’s constant.• This means that a frequency can be 1 “h”, 2 “h”, 3 “h”, and so on, but never 1.2 “h”, 1 1/2 h”, 2 3/4 “h”, 4.56849 “h”, or any other arbitrary number.


• Other physicists did not like this concept. It made no sense, and he gave no reason for it.• Imagine a water wave hitting a beach every 1 minute. Imagine that this water wave, if given enough energy, will instantaneously jump to hitting the beach every 2 minutes - but nothing ever in between.


• Second, that the frequency of light inherently carries energy.• That is, the higher the frequency, the more powerful the wave is.• This is akin to saying a ripple hitting a beach every 5 seconds is more powerful than a tsunami hitting every 2 hours.• Thus, blue and violet light has more energy than red light because it is a higher frequency.


• X-rays have more energy than ultraviolet or blue rays, microwaves have more energy than radio rays, but less than infrared or red rays, and so on.• This solved the ultraviolet catastrophe - and really well at that.


• By having the frequency inherently carry energy, radiation will not be emitted at every possible frequency.• This is because it is easier for the oven to emit at lower frequencies, and if the oven isn’t hot enough, it doesn’t have enough energy to even emit any of the higher frequencies.• This sets a cap on the maximum frequency the oven can emit.


• And, by limiting the number of frequencies by saying they can only come in certain sizes 1 “h”, 2 “h”, etc., there is now a finite number of frequencies for the oven to emit, and thus a finite amount of energy.• No exploding kitchens.


• Max Planck later solved for “h”, finding it to be 0.0000000000000000000000000000000006626068 m2kg/s.• So, a frequency could only increase in energy by whole amounts of the amount above.• This later led to the Planck’s Length - the amount a wavelength could increase or decrease by.• Planck’s Length is 0.000000000000000000000000000000016 mm.


2P

1P


• Physicists refused to accept that such an arbitrary rule - that frequencies could only increase or decrease by discreet amounts - could be how it actually worked.• No one could explain why such a strange rule would exist (they still can’t).• They just thought it was an interesting mathematical trick that worked.• Until another German “scientist” (he was an amateur physicist) came along: Einstein.


• The year was 1905, one of the biggest turning points in physic’s history.• A 26 year-old German working as a Swiss patent-clerk (with a funny shaped head) published over 4 papers in one year.• In March, he solved another problem in physics, and helped launch the end of classical, Newtonian physics.


The Photoelectric Effect


• The photoelectric effect is an effect light has on certain types of metal.• If you shine a light on a piece of metal, the metal will release some of its electrons, which can then flow out to create an electric current.• Scientists theorized that if enough light-energy hit the metal atom, it would excite its electrons enough so that they would actually fly away.


• If red light was shown on the metal, nothing would happen. No matter how bright or intense the light was, no electrons would be freed from the metal.• If blue light, which is a higher frequency, was used, electrons would start flying out of the metal. No matter how weak or small the light was, electrons would continue to fly out of the metal, albeit less of them.


• An good analogy is a beach ball on a beach. • The red light, being a lower frequency, is like a water wave hitting the beach ball every 5 minutes. The blue is like a water wave hitting every 5 seconds.• The intensity of the light is equal to the height of the wave in this analogy.• An intense light is akin to a tsunami, a weak light a slight ripple.


• So, a red wave hitting the beach ball (the electrons), no matter how big, doesn’t cause it to move. Even if it is a tsunami hitting over and over, the beach ball doesn’t move.• However, if a blue wave hits the beach ball, no matter how small, it causes the beach ball to go flying 20 feet away - even if it’s a small ripple.• That was, in effect, what was happening.


• Scientists were again at a loss.• Their current equations predicted that an intense red light should knock out many more electrons than a weak blue one.• Instead, none were knocked out.


• Einstein’s solutions was to stop thinking about light as a wave, and think of it as little particles, he called “quanta”.• He theorized that light could only come in discreet packets of energy, no more, no less.• Using Planck’s ideas, he also claimed that the amount of energy in each packet was related to the frequency of the light.


• A higher frequency light had packets with more energy than a lower frequency light.• This means that the intensity of a light is how many little particles there are, rather than amplitude of a wave.• This extended Planck’s original idea that not only could frequencies come in certain amounts, but the intensity of light could only come in certain discreet amounts.


• So, a light can’t have 32 1/2 photons. Only whole numbers.• Einstein then postulated that a red light can’t knock out any electrons because the individual packets don’t have enough energy.• That is, to knock an electron out of its orbit, a photon has to do it in one shot.• So if one doesn’t have enough energy, neither will 50,000.


• The blue light, however, has enough energy in its photons.• Only one blue photon is required to knock an electron out of its orbit, so no matter how few there are, some electrons will be ejected.


• Einstein’s equations worked.• This through physics into a conundrum:• If light is a particle, then how does the two-split light experiment create an interference pattern, a very wavy thing to do?• Some experiments were done later to try and find out what was going on.• If the individual photons are measured en route to the wall, no interference pattern will develop.


• If one photon is shot at a time, an interference pattern will develop - even though scientists can see that only one particle is going at a time, not a wave.• How is one particle, which can either go through one slit or the other, some how figuring out that there are two slits there and that it should interfere with itself?• How can a particle even interfere with itself?• Why when it was measured did it act like a particle?


• Scientists were forced to accept that light was sort-of-kind-of a particle and a wave at the same time.• There are several theories that attempt to explain them (although none can really be proven).• The Copenhagen Interpretation is the most accepted.


The Copenhagen Interpretation


• This theory states that, when a particle is not being observed, it is actually a wave.• The wave spreads out, ending up in every possible place the particle could go.• At the moment of observation or measurement, the wave “collapses” into a single point, where it is a particle again.


• So, as the photon goes towards the two slits, it is no longer being observed, so it is a wave.• The wave travels through both slits at the same time, and interferes with itself.• This cancels out the wave in certain regions, meaning the wave can’t “collapse” into any point that has been canceled out.• When it hits the wall, it is “observed”, so collapses into a single particle.


• Physicists disagree about whether this is just a handy mathematical trick, or something that actually exists.• But, most don’t care.


• In 1924, a French physicist named Louis-Victor-Pierre-Raymond, 7th duc de Broglie (usually just called Louis de Broglie) claimed that all of matter was sort-of-kind-of a wave, not just light.• In 1927, they repeated the two-slit experiment using electrons instead of light and a crystal instead of two slits.• An interference pattern was created.


• It was tried again with protons, neutrons, and even recently by whole fullerene (buckyball) molecules (60 carbon atoms shaped like soccer balls).• Every time, interference patterns were created, usually something particles can’t do.• This means then, that according to the Standard Model, everything is a wave.• You just can’t tell at large scales, where particle-like properties dominate.


• Some physicists believe that particles are not waves or particles, but something else entirely.• The wave-like nature of particles gives rise to things like tunneling - the ability for a particle to end up on the other side of an impenetrable barrier without going around or through it. It just magically ends up on the other side.

The Standard Model:Quantum Tunneling

The Standard Model:Heisenberg Uncertainty Principle

The Standard Model:Entanglement

The Standard Model:Radiation

The Standard Model:Antimatter

The Standard Model:Dark Matter

The Standard Model:Dark Energy

The Standard Model:Supersymmetry

The Standard Model:The Big Bang

the standard model atomic structure,and the bing banganti-matter,winos,zinos,

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