Book Summary 18— The Grand Design
You can find all my book summaries — here.
1) Mystery of Being
Many theories about universe
M-Theory is a map of many overlapping theories
- this is not the only universe
- created out of nothing
- creation doesn’t need supernatural/god
2) The rule of Law
585 BC — Thales first person who claimed that world can be understood
first prediction of solar eclipse
500 BC — Pythagoras — Law of Hypotenuse and musical string theory
250 BC — Archimedes -
1) Law of the lever
2) Law of buoyancy
3) Law of mirrors
400 BC — Democritus
Law of Inertia
Atomism — everything is made of particles
250 BC — Aristecharius
Sun is much larger and we revolve around sun not other way
Laws of Nature
Mathematical reflection of external reality independent of who looks at it
- but does objective reality exist?
3) What is Reality?
Goldfish in curved fishbowl could have his own theories of laws (curved), which would keep true in his reality
- what makes our reality real?
Matrix and Truman show — could be real?
Every model has its validity as it can explain part of reality
Realism — if we all see it it is real
BUT
Quantum physics — a particle doesn’t have a position nor velocity until measured
If 2 models agree with an observation it is pointless to argue which one is more real — both are.
Just need to choose which one to use for further observations.
Seeing
- just a mental model / visualisation of the environment
We can’t see electrons, but we can see the effects they produce and the models we have have so far explained those effects.
Quark model was even for many phycisicists too much as it’s inpossible to observe, but as the model led to prove obervations right it is now accepted.
A good model:
- elegant
- adjustable elements
- explains all observations
- makes future predications which you can falsify or prove
Einstein — As simple as possible but no simpler
If we disproove future prediction we need a new model!
Latest example
- Our universe is static
Hubble observed that more galaxies are moving away from us than moving in our direction
- In theory could also be that for some yet unknown reason light loses energy over long distances, but we haven’t observed that yet
Light is a Particle and Wave
- 2 models which both are accurate (but yet conflicting?)
This is model-dependent realism
There is a network of theories called the M-theory, they are all good to describe phenomena in their range.
4) Alternative Histories
Quantum physics — things can be particles and waves — dualism
but our laws of Physcis still apply, even though so different.
because they are good approximations of the granular quantum level/model on a larger scale.
Buckyball experiment
- football like particle shot against wall with slits and there was balls were they weren’t supposed to be
-> they are waves
Not likely that object can do it too, but scientists have been experimenting with bigger and bigger particles, hope is to get a virus to pass through a wall at some point
Heisenberg — uncertainty
the more accurately you measure position the less certain is velocity and vice versa
The result of either can never be smaller than Planck’s constant — minimum required
We can’t determine future with certainty.
Nature does it through a process which is fundamentally uncertain.
Our laws determine the probabilities of various futures rather than certainty.
Probabilities in quantum physics are different than Laws of Physics
- they reflect the total randomness of nature
Nobody really understands Quantum physics but it has so far always proven right.
Fundamental randomness means particles are everywhere and nowhere at the same time.
You can’t just observe without interfering.
History of particle
is in double slit experiment simply it’s path
The possibility of observation is contricted from the possibility of all its histories
“sum over histories”
“alternative histories”
Feynman — quantum mechanics
The universe, according to quantum physics, has no single past, or history.
5) The Theory of Everything
First laws
- Newton Gravity
- Faradday Magnetism based on Gravity Force Fields
- Maxwell put the formula around it and discovered that light is an electromagnetic wave
Sun emits all wavelengths
Our eyes adjusted to the ones it emits most
Aliens will probably have eyes which can see wavelengths which their sun emits most (Xrays, Ultrared, Radio, etc)
Einstein
Age 26 — publish “On the electrodynamics of moving bodies”
Laws of physics should be the same for all uniformly moving observers
Special relativity
clocks run faster according to observer who is at rest
Time Dilation
moving clocks run slower
(at every day speed — tiny)
Time is not absolute but relative
Time and space are intertwined
Time is its own dimension
Einstein revised Newtown Gravity into General Relativity
Space-Time is not flat but distorted by mass and energy
When flying from NY to Madrid we don’t fly parallel to equator but on grand circle route
first northeast then east then southeast which is shorter as the earth of a globe
Gravity isn’t attraction of massess but rather distortion of space-time
paths are bent which appears as if bodies attract each other
Need to appy alternative histories of Quantum Physics to General Relativity
4 known forces of nature
1. Gravity — weakest, long range but everything attracts
2. Electromagnetism — long range and stringer than Gravity, but only on electrically charged objects
3. Weak nuclear force — causes radioactivity and vital role in formation of elements in stars
4. Strong nuclear force — holds together protons and neutrons in atoms
developed into Quantum Electrodynamics QED
Feynman invented diagrams which helped account for infinite possibilities
problem was that because its infinite the result was infinite
so dubious renormalisation maths helps and explained Lamb shift (small change in energy in hydrogen)
Holy Grail would be to find one model for all of the 4 theories above
Quantum Chromodynamics — QCD — gave quarks colours
showed asymptotic freedom — strong forces between quarks — week when close but stronger the further apart
People tried Grand Unified Theories
- resulted in finding that protons decayed which hasn’t been proven yet
biggest problem is to explain gravity through quantum physics
because of Heisenberg principle that soace can’t be empty and we can’t accurately measure position and velocity
it can be in vacuum which is minimal energy where quantums flicker in and out of existence
They present a closed loop of particles coming together and moving away from each other
problem for general relativity as that means there’s infinite energy there which would curve universe into infinitely small size
1976 — theory of supergravity
relying on supersymmetry which states hat theres always 2 partners which cancel each other out
but never calculated nor proven
String theory
particles dont have height or width just patterns of vibrations — strings
and are in 10 dimensions not 4 — other 6 in very small size
dimensions infinitely curved and curled so we don’t notice
M-Theory
Master
Miracle
Mystery
nobody knows
has 11 space time dimensions
9 dimensions have p-branes (p = 0–9) with shapes
dimensions can’t be curled up
allows for different universes with different apparent laws about 10⁵⁰⁰
6) Choosing our Universe
Universe is expanding and it should have been in one place at the beginning — Big Bang
Expanding means no new space is created but the distance between two points isngetting further away
- like the surface of a growing balloon
The farther away from us the faster moving away from us
- but galaxies stay together (the cluster) and within them they don’t move apart
Space at big bang expanded insanely fast
speed doesn’t apply to space expansion
we can find remenants of old universe
Origin of universe was a quantum event
Gravity warps space-time
Time is just another dimension and doesn’t behave the way we understand time — it could warp all the way around or more likely there was no time at the beginning
Quantum physics of alternative histories — the event with highest probability occurred
- each one had their own laws of nature (different dimensions)
Why can’t we see the other 7 dimensions?
- curled up but why?
maybe all dimensions started small and only 4 expanded
7) The Apparent Miracle
- 1 Sun
Most solar systems 2+ suns which makes it almost impossible to have sustained reasonable temperatures
- Circular orbit
2% off 0 — so hardly an ellipse but almost completely a circle
Planet tilt bigger temperature effect than the slightly farther away distance
- Size
size of sun to earth is perfect re mass attraction
- Goldilocks zone
zone which allows for water
- Right elements
lifeforms as we know them need carbon
carbon is only produced when stars run out of helium and then expode in supernovas to catapult the carbon into friendlier places than the sun
- Natures of law
if they only different slightly carbon and life might have never existed
- Number of dimensions
orbit would have been screwed up in anything more than 3 dimensions
Belief is that there is many universes and we are one of them.
8) The Grand Design
Why do we exist?
- God created us?
- but then who created god?
Game of Life
- if you have set conditions you can basically predict what’s going to happen as it will follow pattern loops
- it is possible to have shapes which self-replicate under the right conditions
Energy cancels each other out — positive cs negative.
Star implodes negative energy countered with black hole full of positive energy.
Gravity shapes time and space — allows space time to be locally stable but globally unstable.
Supersymmetry — everything in pairs
On the scale of the entire universe the posiice energy of matter can be balanced our by the negative gravitational energy — that’s why whole universes can come out of nothing.
- spontaneous creation
You can find all my book summaries — here.
