Annotations on Knowing The Nature of Physical Law by Michael Munowitz
Physical Law: conclusions usually based on experiment and observation over many years that have been accepted as universal (Are there physical laws in math or by definition there cannot be because mathematical theories are not observable? If mathematical laws are often based on "intuition" (despite formalists claims to the opposite) can they ever be considered laws? What sets math outside the other physical sciences, I guess, it isn't physical). Godel's Law says that in any formal system adequate for number theory there exists an undecidable formula whose negation is not possible (anti positivist given that positivists believed that theories must be falsifiable to be good theories). If in the formal system (defined within itself) leaves out some formula than how is that formula decided? Is it intuition? God? (These notes derive from Incompleteness by Rebecca Goldstein).
What Knowing asks is "what is knowing and how do we know?" Essential epistemological questions. Godel's Law seems to have called this into question in some essential way because it suggests that there is something outside of our knowing if knowing is defined as empirical. Is there any other kind of knowing?
Preface
"Mathematics of all the languages stands alone" (p, xi). What makes math so special? Mathematics is essential to understanding the universe. It is the "structure" of the universe. And yet, it is buttressed by "undecidable formulas". A Priori knowledge, kno
wledge that comes from understanding (intuition) and not through observation. How do we ever trust "understanding"? Knowing is positing that we can understand at least a little how the universe is put together without understanding or using math.
Chapter 1 Great Expectations--nothing in this chapter
Chapter 2 Ties That Bind (Mass exerts force on space time--otherwise known as gravity)
All particles have mass. Mass is what makes something exist. Existing things are attracted to other existing things (gravity). The more mass, the greater the attractions (mars does not have as much mass so gravity is much less of a factor on Mars than on Earth). In fact, double the mass and double the attraction (but how is it that matter and energy bend space time and that is called gravity. Matter distorts space and mass is matter so mass distorts space as well. these "distortions" are gravity. So what appears as a straight line is actually curves these curves we call "gravity", and are in fact matter distortions of space). All mass distorts space, the heavier the mass the bigger the distortion (which is just another way of saying the bigger the object the greater the gravity attraction) so back to our Mars example, on Mars there are less distortions in space time because there is less matter/mass/energy).
And if the mass is too small to exert force. . . we have electric and magnetic potentials: Even though all matter has mass (including the smallest neutrino), very small particles do not have enough force to come together on their own so this is where the electromagnetic interaction comes into play. An electrically charged particle throws up an electric potential to which other electrically charged particles respond (protons, electrons). The particles in motion create a magnetic potential to which other particles in motion respond. We use electric potentil to describe particles at rest and a magnetic potential to describe particles in motion.
Like with mass, the electrical attraction decreases as distance increases. Larger charges exert greater influence, double the charge double the influence. However, because there are both negative and positive charges eventually the attraction becomes neutral as the positive and negative charges balance one another out forming what appears to us to be a solid, stable "mass".
Small differences in structure of electrons and protons create big differences in behavior of particles. The electric potential creates all the structures in the universe
But still, there is something beyond gravity and the electrical potential. Something must hold together the protons in a nucleus which are repelling each other as they get closer and closer together, and the electrical potential cannot do that. This thing is the Strong Nuclear Force and it allows the protons and neutrons to exist close together in the nucleus without blowing each other apart (unless, of course, we set off a nuclear bomb). The Strong nuclear force ignores electrons all together and instead treats protons and neutrons alike allowing them to get all snuggled close together and hold on tightly to each other in a very intricate balance that if disturbed will create a very strong repulsion. The Strong Nuclear force operates only when the protons and neutrons are very close, once they move outside that tight orbit the electrical force takes over again.
In all interactions between protons and neutrons in the electric and the strong nuclear force, the actual protons and neutrons are never divided. But, in some interactions we can see that a neutron turns into a proton and creates an antineutrino undergoing beta decay. None of these forces can explain such a process, so into the equation comes the weak nuclear force. The weak nuclear force is characterized by the transformation of a neutron into a proton. It is called weak because it can only exert its influence over very, very small distances. We notice when we look closely at this process that there is another smaller particle in play, the quark.
A quark, still not the smallest, has gravity, an electrical charge and a strong and weak nuclear interaction charge. There are six types of quarks but only two, the up and down, play a role in building protons and neutrons into matter. An up quark carries an electric charge of +2/3 and a down quark carries one of -1/3, so to create a proton, you need two up quarks and one down; to create a neutron it takes one up and two downs to create 0. Each trio of quarks presents itself as one particle bound by the electric force. The weak interaction sometimes subverts the nicely constructed threesomes, and transforms a down quark into an up and the neutron into a proton letting loose an electron and an antineutrino (the strong force is not involved because the electron and antineutrino do not carry a strong interaction charge).
We know these interactions are going on, but what we have to ask is how? Perhaps, we might suggest, it is space itself that tells these guys what to do and when. What if each particle can erect a "field" that can both carry and transmit signals. The particles are computers and the field is what links them (their internet if you will). If this is the case, then the communication is indirect, local and delayed. The message remains even if the particle itself has receded because the message is now in the field. There is a constant interchange of information.
Chapter 3 In the Eye of the Beholder
Relativity does not mean that the world is different depending on your perspective. Nature is the same no matter who is watching from where.
Space has no beginning or end, no ground zero. All points are created equal. What is shared and universal is the distance between reference frames. This distance has to be the same no matter where it is measured, by whom or how. Our spatial frame of reference, our universe, must be symmetric under translation, time and rotational (p. 50). Even if our perspectives appear different, we have to be able to reconcile those differences because nature is NOT different. Einstein's theory of relativity gives us an equation to reconcile the perceived differences.
To be a valid physical law, a descriptive equation cannot change with changes in time or space or observer; it must respect the invariance of the space-time interval
symmetric under translation means that they do not differ depending on the perspective. The universal natural laws remain the same
Chapter 4 Three Part Invention
Three regimes: Newtonian universe which is a clockwork universe; the chaotic machine which is unpredictable; and the quantum machine which runs on probability
In the Newtonion universe there is no free will. Nature's laws act regardless of any position, participant etc.
Inertia: objects at rest remain at rest and objections in motion remain in motion unless disrupted by a force
Potential energy is the energy of position
Kinetic energy is the energy of motion
Mass has a certain potential
Force is difference in potential. Force is the produce of mass and acceleration. Force is the rate at which momentum changes. The bigger the change in momentum, the bigger the force needed to produce it. The faster the variation, the bigger the force.
Energy must remain the same in the universe. Law of conservation. If we have no outside force, momentum stays the same. If an object hits another object, there is no change in total momentum (this is why a gun recoils when it shoots; the force of the bullet acts on the gun).
Velocity: how much and in what direction the position changes from instant to instant. A twofold change in velocity requires a four fold change in kinetic energy (its exponential). Change in potential is to do work, applying force over distance. Any change of energy in one place is balance by a change of energy in another because of conservation of energy.
Space matters in the Newtonian universe. Object is position in both time and space, so it might have inertia in time but be moving in space (this is what happens when the moon is orbiting and why it is that the moon does not collapse into the earth due to gravity. The earth has a larger mass than the moon and thus undergoes proportionally less acceleration and appears not to be moving even though it is. The moon, smaller moves more quickly)
Twice the applied force is twice the acceleration, it's a one to one relationship. Twice the mass, 1/2 the acceleration and it is cumulative so with three particles the acceleration is cut to a third because each particle resists individually
Matter resists force, however, with inertia. The more mass, the more inerita. This is why all objects fall at the same speed: the more mass the more inertia is being worked on the mass; the less mass the more slowly it falls.
And so, Newton's second law emerges, as acceleration, force and mass interact to conserve the energy.
Chapter 5 Mass as Medium, p. 98
All of newton's laws do not hold up when we get up to speeds approaching the speed of light, there we have to enter the quantum universe (laws of conservation of momentum do hold).
Einstein determined that mass is a medium in which to store energy and that energy can be congealed in mass. And gravity is not a force afterall but the effects of mass on space time causing space time to curve.
A scalar has size but not direction (temperature has a size but no direction, distance, time). They do not change if we reorient space.
A vector has size and direction and they do change if space is reoriented
THis chapter is very confusing
As we approach the speed of light, space time merges
In the vacuum of space far from any large mass to exert its pull on us acceleration actually does the same thing making it appear as if gravity is involved. The principle of equivalence states that gravity and inertia are the same thing and thus gravitational mass and inertial mass are nothing but mass.
In the Newtonian world, space is a construct that has no affect on universal forces. In the Quantum world, mass warps space time and it does have a role
Geodisic is the straightest path on a curved surface (the universe)
Newton was correct but what he didn't do is explain how it was there was a thing he called "gravity". General relativity connects mass with the curvature of space time to show what's happening when we say "gravity". Mass creates a distortion in space time that is proprotional to its distance and its weight.
Chapter 6 Taking Charge, p. 132
Electric charges have no mass and thus are not affected by gravity but their force is much more powerful. All fundamental particles preserve their electric charges and the grand total of all charges in the universe is zero. Electric charge is strictly conserved.
All matter consists of electric charges
Electricstatic field comes from electric charges at rest
magnetic fields come from electric charges in motion
The two are immutably connected
The bigger the charge the bigger the electrostatic force, double the charge, double the force
Electrostatic force decreases exponentially as distance increases (inverse square law)
Inverse square laws arise anywhere that a given influence radiates outward from a central source symmetrically in all directions
A changing electric field gives rise to a magnetic field and vice versa
Maxwell's four laws tell us all we need to know of magnetic and electric fields in the Newtonian universe
When the electrostatic field is disrupted, waves form; electric energy is radiated and a magnetic field is tagging along (and vice versa)
A change in an electrostatic field comes from a particle undergoing accelerated motion
What is a wave?
Waves have a frequencey, a wavelength, an amplitude and a phase
A wave is not a particle. A wave is uncertain and can be in more than one place at one time (unlike a particle), waves can increase one another, has a phase and can interfere and be additive with another wave, can cancel each other out, can bend
Chapter 7 Never Certain, p. 162 Switch from the macro to the micro world
In the quantum world, we are faced with probabilities because particles are waves and waves are unpredictable
Nothing is certain because every observation is interfered with or disturbed by the observer.
A photon delivers one quantum of energy. Quantum measurement depends on energy X time or Momentunm X length
Heisenberg's uncertainty principle: we can know position but not momentum; we can know momentum but not position. If we multiple the uncertainties in both the momentum and position, we get h, plank's constant (roughly). The uncertainty in position varies in inverse proportion to the uncertainty in momentum. We take measurements at given times and then we average them to get a probability.
Chapter 8 The Path Not Taken
The probabilities of any quantum state must account for all possibilities.
Left alone, in the quantum mechanical system particles do not move randomly. It is predetermined. However, when we go to measure the particle, it is no longer left alone and we must rely on the probability that something will happen not the certainty. "A world of possibilities collapses into a single realty for the intrusive observer" (p. 209)
Chapter 9 Symmetry Perforce, p. 210
Nature imposes symmetries on quantum mechanical states. Symmetries introduce constraints. The world cannot be anything/everything. It has to follow rules and those rules impose constraints.
Pauli principle: either the state of a system is symmetric with respect to interchange of identical particles (like a wave that you can fold and it will track on top of each other; it looks teh same left-right) or it is antisymmetric-it appears inverted (p. 216)
Particles that are symmetric are called Bosons and they can occupy the same quantum state. Photons. Bosons tend to remain isolated
Antisymmetric particles are called Fermions and no two can occupy the same quantum state unless they possess opposite spins. Electrons and quarks. Fermions tend to be social. This is why electrons can jump from layer to layer in an atom. Spin determines how friendly the atom is. Some are very friendly and others not so much.
Symmetry: the changes in a system are such that the system does not function differently after the changes are made. All parts of the system change in the same proportionate way. There can be local symmetry and global symmetry. Nature is such that changes in a local system do not impair the symmetry of physical laws elsewhere. In order for this to work, forces must be in charge of maintaining this local symmetry: these forces are gravity, electromagnetism, and the strong and weak nuclear forces.
Chapter 10 Ends and odds, p. 241
Time is a product of the trend toward chaos, the arrow points in the direction of greater disorder because there are always more ways that particles can spread out. It is much more statistically likely that particles will spread out and become evenly distributed (probabilistic nirvana) then it is that they will clump and not move. This spreading is entropy and is time.
Energy lasts forever
Energy does not equal work. Some energy is always lost when work is performed, lost in heat. So energy is equal to work + heat. THis is the first law of thermodynamics.
In the microworld, in contrast, the difference between work and heat is the difference between organized and disorganized motion.
States go from order to disorder and not from order to more order
2nd law of thermodynamics: work dissipates into heat but heat does not turn into work
Nature demands that we stir up the surroundings outside the equilibrium state in order to ensure the equilibrium state and this "stirring up" necessitates heat. Thus, heat is always lost when we work
Later is a world with greater entropy
Chapter 11 Surprise Endings, p. 268
Chaos plays a role
Chapter 12 Loose Ends, p. 284
We still haven't found a way to include gravity in the quantum view
Dopler effect: crests that are moving toward an observer arrive with greater frequency (seem to get louder) then those form a source moving away. All waves do it, not just sound waves
Inflation: The universe itself is expanding (not just what is in the universe, which is also expanding, but the container is expanding too)
Dark matter: there is not enough mass in the universe to account for the structure of the universe gravitationally, dark matter is a theory about the remaining mass that is missing
Dark energy: energy is also missing that causes a gravitational repulsion
Standard model can account well enough for the electromagnetic and weak and strong nuclear forces using a spare set of fermions and bosons but it does not account for gravity, dark energy or matter or the unification of the strong and weak nuclear forces
Supersymmetry--what if all the major fermions and bosons had a buddy in the opposing camp
String theory--tiny, smaller than planck size vibrating energies in a world of eleven dimensions
Some terms to understand
symmetry--viewed from any perspective, they all look the same (quickly after the big bang, gravity, electromagnetism, the strong and the weak nuclear force all were formed and merged into a superunified quantum fieldof perfect symmetry, p. 298). Then almost as quickly, the unity dissolved and the forces began to be distinguished one from the other. An object is invariant (doesn't vary) in a transformation, but what exactly is meant by doesn't vary?
singularity-I'm a bit confused by this term. I read it in technological books/articles and it seems to be suggesting a time when technology and humans become one. But it physics, it seems to be talking about a unified theory of all things. . .but then I see it used to refer to black holes too. So I'm not really sure what the singularity is (maybe there are many of them)
What Knowing asks is "what is knowing and how do we know?" Essential epistemological questions. Godel's Law seems to have called this into question in some essential way because it suggests that there is something outside of our knowing if knowing is defined as empirical. Is there any other kind of knowing?
Preface
"Mathematics of all the languages stands alone" (p, xi). What makes math so special? Mathematics is essential to understanding the universe. It is the "structure" of the universe. And yet, it is buttressed by "undecidable formulas". A Priori knowledge, kno
wledge that comes from understanding (intuition) and not through observation. How do we ever trust "understanding"? Knowing is positing that we can understand at least a little how the universe is put together without understanding or using math.
Chapter 1 Great Expectations--nothing in this chapter
Chapter 2 Ties That Bind (Mass exerts force on space time--otherwise known as gravity)
All particles have mass. Mass is what makes something exist. Existing things are attracted to other existing things (gravity). The more mass, the greater the attractions (mars does not have as much mass so gravity is much less of a factor on Mars than on Earth). In fact, double the mass and double the attraction (but how is it that matter and energy bend space time and that is called gravity. Matter distorts space and mass is matter so mass distorts space as well. these "distortions" are gravity. So what appears as a straight line is actually curves these curves we call "gravity", and are in fact matter distortions of space). All mass distorts space, the heavier the mass the bigger the distortion (which is just another way of saying the bigger the object the greater the gravity attraction) so back to our Mars example, on Mars there are less distortions in space time because there is less matter/mass/energy).
And if the mass is too small to exert force. . . we have electric and magnetic potentials: Even though all matter has mass (including the smallest neutrino), very small particles do not have enough force to come together on their own so this is where the electromagnetic interaction comes into play. An electrically charged particle throws up an electric potential to which other electrically charged particles respond (protons, electrons). The particles in motion create a magnetic potential to which other particles in motion respond. We use electric potentil to describe particles at rest and a magnetic potential to describe particles in motion.
Like with mass, the electrical attraction decreases as distance increases. Larger charges exert greater influence, double the charge double the influence. However, because there are both negative and positive charges eventually the attraction becomes neutral as the positive and negative charges balance one another out forming what appears to us to be a solid, stable "mass".
Small differences in structure of electrons and protons create big differences in behavior of particles. The electric potential creates all the structures in the universe
But still, there is something beyond gravity and the electrical potential. Something must hold together the protons in a nucleus which are repelling each other as they get closer and closer together, and the electrical potential cannot do that. This thing is the Strong Nuclear Force and it allows the protons and neutrons to exist close together in the nucleus without blowing each other apart (unless, of course, we set off a nuclear bomb). The Strong nuclear force ignores electrons all together and instead treats protons and neutrons alike allowing them to get all snuggled close together and hold on tightly to each other in a very intricate balance that if disturbed will create a very strong repulsion. The Strong Nuclear force operates only when the protons and neutrons are very close, once they move outside that tight orbit the electrical force takes over again.
In all interactions between protons and neutrons in the electric and the strong nuclear force, the actual protons and neutrons are never divided. But, in some interactions we can see that a neutron turns into a proton and creates an antineutrino undergoing beta decay. None of these forces can explain such a process, so into the equation comes the weak nuclear force. The weak nuclear force is characterized by the transformation of a neutron into a proton. It is called weak because it can only exert its influence over very, very small distances. We notice when we look closely at this process that there is another smaller particle in play, the quark.
A quark, still not the smallest, has gravity, an electrical charge and a strong and weak nuclear interaction charge. There are six types of quarks but only two, the up and down, play a role in building protons and neutrons into matter. An up quark carries an electric charge of +2/3 and a down quark carries one of -1/3, so to create a proton, you need two up quarks and one down; to create a neutron it takes one up and two downs to create 0. Each trio of quarks presents itself as one particle bound by the electric force. The weak interaction sometimes subverts the nicely constructed threesomes, and transforms a down quark into an up and the neutron into a proton letting loose an electron and an antineutrino (the strong force is not involved because the electron and antineutrino do not carry a strong interaction charge).
We know these interactions are going on, but what we have to ask is how? Perhaps, we might suggest, it is space itself that tells these guys what to do and when. What if each particle can erect a "field" that can both carry and transmit signals. The particles are computers and the field is what links them (their internet if you will). If this is the case, then the communication is indirect, local and delayed. The message remains even if the particle itself has receded because the message is now in the field. There is a constant interchange of information.
Chapter 3 In the Eye of the Beholder
Relativity does not mean that the world is different depending on your perspective. Nature is the same no matter who is watching from where.
Space has no beginning or end, no ground zero. All points are created equal. What is shared and universal is the distance between reference frames. This distance has to be the same no matter where it is measured, by whom or how. Our spatial frame of reference, our universe, must be symmetric under translation, time and rotational (p. 50). Even if our perspectives appear different, we have to be able to reconcile those differences because nature is NOT different. Einstein's theory of relativity gives us an equation to reconcile the perceived differences.
To be a valid physical law, a descriptive equation cannot change with changes in time or space or observer; it must respect the invariance of the space-time interval
symmetric under translation means that they do not differ depending on the perspective. The universal natural laws remain the same
Chapter 4 Three Part Invention
Three regimes: Newtonian universe which is a clockwork universe; the chaotic machine which is unpredictable; and the quantum machine which runs on probability
In the Newtonion universe there is no free will. Nature's laws act regardless of any position, participant etc.
Inertia: objects at rest remain at rest and objections in motion remain in motion unless disrupted by a force
Potential energy is the energy of position
Kinetic energy is the energy of motion
Mass has a certain potential
Force is difference in potential. Force is the produce of mass and acceleration. Force is the rate at which momentum changes. The bigger the change in momentum, the bigger the force needed to produce it. The faster the variation, the bigger the force.
Energy must remain the same in the universe. Law of conservation. If we have no outside force, momentum stays the same. If an object hits another object, there is no change in total momentum (this is why a gun recoils when it shoots; the force of the bullet acts on the gun).
Velocity: how much and in what direction the position changes from instant to instant. A twofold change in velocity requires a four fold change in kinetic energy (its exponential). Change in potential is to do work, applying force over distance. Any change of energy in one place is balance by a change of energy in another because of conservation of energy.
Space matters in the Newtonian universe. Object is position in both time and space, so it might have inertia in time but be moving in space (this is what happens when the moon is orbiting and why it is that the moon does not collapse into the earth due to gravity. The earth has a larger mass than the moon and thus undergoes proportionally less acceleration and appears not to be moving even though it is. The moon, smaller moves more quickly)
Twice the applied force is twice the acceleration, it's a one to one relationship. Twice the mass, 1/2 the acceleration and it is cumulative so with three particles the acceleration is cut to a third because each particle resists individually
Matter resists force, however, with inertia. The more mass, the more inerita. This is why all objects fall at the same speed: the more mass the more inertia is being worked on the mass; the less mass the more slowly it falls.
And so, Newton's second law emerges, as acceleration, force and mass interact to conserve the energy.
Chapter 5 Mass as Medium, p. 98
All of newton's laws do not hold up when we get up to speeds approaching the speed of light, there we have to enter the quantum universe (laws of conservation of momentum do hold).
Einstein determined that mass is a medium in which to store energy and that energy can be congealed in mass. And gravity is not a force afterall but the effects of mass on space time causing space time to curve.
A scalar has size but not direction (temperature has a size but no direction, distance, time). They do not change if we reorient space.
A vector has size and direction and they do change if space is reoriented
THis chapter is very confusing
As we approach the speed of light, space time merges
In the vacuum of space far from any large mass to exert its pull on us acceleration actually does the same thing making it appear as if gravity is involved. The principle of equivalence states that gravity and inertia are the same thing and thus gravitational mass and inertial mass are nothing but mass.
In the Newtonian world, space is a construct that has no affect on universal forces. In the Quantum world, mass warps space time and it does have a role
Geodisic is the straightest path on a curved surface (the universe)
Newton was correct but what he didn't do is explain how it was there was a thing he called "gravity". General relativity connects mass with the curvature of space time to show what's happening when we say "gravity". Mass creates a distortion in space time that is proprotional to its distance and its weight.
Chapter 6 Taking Charge, p. 132
Electric charges have no mass and thus are not affected by gravity but their force is much more powerful. All fundamental particles preserve their electric charges and the grand total of all charges in the universe is zero. Electric charge is strictly conserved.
All matter consists of electric charges
Electricstatic field comes from electric charges at rest
magnetic fields come from electric charges in motion
The two are immutably connected
The bigger the charge the bigger the electrostatic force, double the charge, double the force
Electrostatic force decreases exponentially as distance increases (inverse square law)
Inverse square laws arise anywhere that a given influence radiates outward from a central source symmetrically in all directions
A changing electric field gives rise to a magnetic field and vice versa
Maxwell's four laws tell us all we need to know of magnetic and electric fields in the Newtonian universe
When the electrostatic field is disrupted, waves form; electric energy is radiated and a magnetic field is tagging along (and vice versa)
A change in an electrostatic field comes from a particle undergoing accelerated motion
What is a wave?
Waves have a frequencey, a wavelength, an amplitude and a phase
A wave is not a particle. A wave is uncertain and can be in more than one place at one time (unlike a particle), waves can increase one another, has a phase and can interfere and be additive with another wave, can cancel each other out, can bend
Chapter 7 Never Certain, p. 162 Switch from the macro to the micro world
In the quantum world, we are faced with probabilities because particles are waves and waves are unpredictable
Nothing is certain because every observation is interfered with or disturbed by the observer.
A photon delivers one quantum of energy. Quantum measurement depends on energy X time or Momentunm X length
Heisenberg's uncertainty principle: we can know position but not momentum; we can know momentum but not position. If we multiple the uncertainties in both the momentum and position, we get h, plank's constant (roughly). The uncertainty in position varies in inverse proportion to the uncertainty in momentum. We take measurements at given times and then we average them to get a probability.
Chapter 8 The Path Not Taken
The probabilities of any quantum state must account for all possibilities.
Left alone, in the quantum mechanical system particles do not move randomly. It is predetermined. However, when we go to measure the particle, it is no longer left alone and we must rely on the probability that something will happen not the certainty. "A world of possibilities collapses into a single realty for the intrusive observer" (p. 209)
Chapter 9 Symmetry Perforce, p. 210
Nature imposes symmetries on quantum mechanical states. Symmetries introduce constraints. The world cannot be anything/everything. It has to follow rules and those rules impose constraints.
Pauli principle: either the state of a system is symmetric with respect to interchange of identical particles (like a wave that you can fold and it will track on top of each other; it looks teh same left-right) or it is antisymmetric-it appears inverted (p. 216)
Particles that are symmetric are called Bosons and they can occupy the same quantum state. Photons. Bosons tend to remain isolated
Antisymmetric particles are called Fermions and no two can occupy the same quantum state unless they possess opposite spins. Electrons and quarks. Fermions tend to be social. This is why electrons can jump from layer to layer in an atom. Spin determines how friendly the atom is. Some are very friendly and others not so much.
Symmetry: the changes in a system are such that the system does not function differently after the changes are made. All parts of the system change in the same proportionate way. There can be local symmetry and global symmetry. Nature is such that changes in a local system do not impair the symmetry of physical laws elsewhere. In order for this to work, forces must be in charge of maintaining this local symmetry: these forces are gravity, electromagnetism, and the strong and weak nuclear forces.
Chapter 10 Ends and odds, p. 241
Time is a product of the trend toward chaos, the arrow points in the direction of greater disorder because there are always more ways that particles can spread out. It is much more statistically likely that particles will spread out and become evenly distributed (probabilistic nirvana) then it is that they will clump and not move. This spreading is entropy and is time.
Energy lasts forever
Energy does not equal work. Some energy is always lost when work is performed, lost in heat. So energy is equal to work + heat. THis is the first law of thermodynamics.
In the microworld, in contrast, the difference between work and heat is the difference between organized and disorganized motion.
States go from order to disorder and not from order to more order
2nd law of thermodynamics: work dissipates into heat but heat does not turn into work
Nature demands that we stir up the surroundings outside the equilibrium state in order to ensure the equilibrium state and this "stirring up" necessitates heat. Thus, heat is always lost when we work
Later is a world with greater entropy
Chapter 11 Surprise Endings, p. 268
Chaos plays a role
Chapter 12 Loose Ends, p. 284
We still haven't found a way to include gravity in the quantum view
Dopler effect: crests that are moving toward an observer arrive with greater frequency (seem to get louder) then those form a source moving away. All waves do it, not just sound waves
Inflation: The universe itself is expanding (not just what is in the universe, which is also expanding, but the container is expanding too)
Dark matter: there is not enough mass in the universe to account for the structure of the universe gravitationally, dark matter is a theory about the remaining mass that is missing
Dark energy: energy is also missing that causes a gravitational repulsion
Standard model can account well enough for the electromagnetic and weak and strong nuclear forces using a spare set of fermions and bosons but it does not account for gravity, dark energy or matter or the unification of the strong and weak nuclear forces
Supersymmetry--what if all the major fermions and bosons had a buddy in the opposing camp
String theory--tiny, smaller than planck size vibrating energies in a world of eleven dimensions
Some terms to understand
symmetry--viewed from any perspective, they all look the same (quickly after the big bang, gravity, electromagnetism, the strong and the weak nuclear force all were formed and merged into a superunified quantum fieldof perfect symmetry, p. 298). Then almost as quickly, the unity dissolved and the forces began to be distinguished one from the other. An object is invariant (doesn't vary) in a transformation, but what exactly is meant by doesn't vary?
singularity-I'm a bit confused by this term. I read it in technological books/articles and it seems to be suggesting a time when technology and humans become one. But it physics, it seems to be talking about a unified theory of all things. . .but then I see it used to refer to black holes too. So I'm not really sure what the singularity is (maybe there are many of them)
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