Post on 16-Dec-2015
Max Tegmark, MITMax Tegmark, MIT
Why I think that we live in a mathematical objectWhy I think that we live
in a mathematical object
Can we describe reality purely mathematically?Can we describe reality purely mathematically?
But can we understand all this in terms of a fundamental “theory of everything”?
But can we understand all this in terms of a fundamental “theory of everything”?
gr-qc/9704009
0704.0646 [gr-qc]
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Do you yearn for a TOE with an intuitive interpretation?
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Do you yearn for a TOE with an intuitive interpretation?
Opposition is good, in the dialectic spirit
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Do you yearn for a TOE with an intuitive interpretation?
Thus spake the bards:
Forget it!
Opposition is good, in the dialectic spirit
“It’s all just the equations”
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
Mathematical Universe Hypothesis (MUH):
Or external physical reality is a mathematical structure.
Mathematical Universe Hypothesis (MUH):
Or external physical reality is a mathematical structure.
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
TOE
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
TOE
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
For this description of the external physical reality to be complete, it must be devoid of human “baggage”.
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
TOE
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
We humans have a common understanding of words like“object”, “experiment”, “observation”, “cause”, “particle”, “string”, but computers don’t!
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Big Bang Zoom
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Big Bang Zoom
Tegmark & Wheeler 2001, quant-ph/0101077
Less baggage
More baggage
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Big Bang Zoom
Tegm
ark 1997, gr-qc/9704009, Ann. P
hys, 270, 151A mathematical structure: abstract entities with relations between themA mathematical structure: abstract entities with relations between them
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
External Reality Hypothesis (ERH):
There exists an external physical reality completely independent of us humans.
Mathematical Universe Hypothesis (MUH):
Or external physical reality is a mathematical structure.
Mathematical Universe Hypothesis (MUH):
Or external physical reality is a mathematical structure.
Phenomenology implications
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Big Bang Zoom
Tegmark 1997, gr-qc/9704009, Ann. Phys, 270, 151
Tegmark 1997, gr-qc/9704009, Ann. Phys, 270, 151
Bird’s view: Frog’s view:
Emergence implications
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
•Is it really possible to derive “physics from scratch”, i.e., frog’s view from bird’s view?
• How would physics emerge from the mathematical structure?
• Promising 1st steps: automorphism group, symmetries, irracs & irreps, etc.
• Gödel completeness/Church-Turing computability may help explain why the laws of our universe are so simple.
Parallel universe
implications
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
This isn’t science!
It’s inevitable
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
I hate it!
Makes sense! Why not?
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Party on!
If our frog’s view of our observable universe…
…requires more bits to describe than…
…the bird’s view of our mathematical structure…
…then we’re in a multiverse!
10100
bits?103
bits?
So if you’re looking for a simple
mathematical TOE, you’re looking for a multiverse theory.
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
Big Bang Zoom
Where are the parallel universes?
1) Far away in space
2) Infinitely far away in space
3) Elsewhere in Hilbert space
4) Elsewhere in “math space”
Big Bang Zoom
What are the 4 multiverse levels like?
1) Same effective laws of physics, different initial conditions
2) Same fundamental laws of physics, different effective laws (“bylaws”)
3) Nothing qualitatively new
4) Different fundamental laws of physics
The bigger the multiverse, the simpler the theory.
10100 bits?
103 bits?
0 bits!
102 bits?
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
More MUH
support
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
We’re not
taking this guy seriously enough!
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
The strongest form of the anthropic principle:
“The Universe must be such that we like it.”
Max TegmarkDept. of Physics, MIT
tegmark@mit.eduFQXi Symposium
July 22, 2007
The strongest form of the anthropic principle:
“The Universe must be such that we like it.”
0704.0646 [gr-qc]