Transcript Is the moon up there when we are not looking?

Is the moon up there when we are not looking?
Overview
 QM suggests that the observer/experimenter has an effect
on the observed.
 The observer may even change the past as suggested by the
so-called delayed choice experiment.
 The following is a quick review of the preceding sections.
Dx DP ≥ h
Measuring one of a complementarity pair features of
an object disturbs the system such that the other
feature acts bizarre.
Superposition of states
 A quantum system is in all probable states at the same
time.
 For example, an electron, before detection, is believed
to spin clockwise and counterclockwise about all
possible axes at the same time.
State reduction
 Upon detection by the experimenter, the electron exhibits
spinning in only one direction along the trajectory of the
detecting photon.
Entanglement
spooky action in the distance
 If one of the entangled photons is measured to have a
clockwise spin, the other entangled pair will show
counterclockwise spin immediately, even if the
photons are worlds apart.
 In 2009, researchers at the USC at Santa Barbara
demonstrated entanglement between two big
objects visible by naked eye.
Quantum Zeno effect
 If a system that normally decays to a lower state, is
watched very early in the process, it almost stays in its
original state. If it is watched constantly,
it virtually never decays.
 The act of us watching stops the
clock
 A watched pot never boils!!
Wheeler’s Delayed Choice experiment
 Today’s choice changes the past
 Does the future affect the past?
Possible Solutions
1/ The world is in a classical state. Superposition of states
of quantum mechanics is wrong.
2/ The world is in quantum superposition of states,
Observers actually reduce it to one classical state.
3/ The world exists is in superposition of states. The
observer perceives just one state.
Possible Solutions
4/ There is a common phenomenon shared by all
observers which leads to the progression of state
reductions and evolution of the universe.
5/………..
 Followings are different interpretations offered by
physicists.
 Choose one of them and make it your own.
Copenhagen interpretation
Physics is not concerned with how nature is, it talks about
what we can say about nature.
Shut up and Calculate
Many worlds
 Super-position is real. There are many collapses to
many probable single states.
 Every state starts a new universe.
 Many copies of observers continue on each new
branch of the universe.
Bohm’s quantum potential
There is no super-position.
There is just one process, no need to divide it to wave or
particle.
The process is governed by quantum potential.
Bohemian Mechanics continued…..
Humans are physical objects who are influenced by
quantum potential and influence it as well.
Our mental processes create our own realities.
Penrose –Hamerof Theory of
Consciousness
 The theory defies the classical approach where
awareness is mere the product of physical processes of
the brain.
 Solitons are waves in microtubules.
Continued.....
 Recent experiments has found vibrations in
megahertz range in microtubules.
 The experiments suggests that EEG rhythms (brain
waves) also derive from deeper level microtubule
vibrations.
Is consciousness a separate entity from what we call
physical domain?
Microtubules
 The theory accepts the superposition and suggests that
consciousness reduces it to one classical state.
 Therefore, it conveys that our consciousness actually
participates in forming the reality as we see it.
 Does consciousness actually collapses the wave function?
 Are microtubules a mean for consciousness to connect or
act on quantum domain?
Transactional Interpretation
 There is a wave going backward in time as well (answer
for Wheeler’s delayed choice experiment)
 The universe is evolving due to signals that go back and
forth.
 No Observers: Transactions involving observers are no
different from other transactions. (solution for observer
problem)
Transactional Interpretation
 No Paradoxes: Transactions are intrinsically
nonlocal.(solution for quantum entanglement)
 Universe constantly evolves. No superposition. An
ever-changing but one state universe.
 Are the assumptions acceptable to you?
 Can future affect the past?
Henry Stapp Views
 Observer receives a smear of possibilities
 Experimenter asks a question, nature answers yes or
no (collapse of the wave function)
 Observation chooses a history out of sum over
histories (retro causal effect)
 Nature somehow wants to please the observer (follows
his/her desire. Good for gamblers)
Henry Stapp Views
 Consciousness is something added over and above physical
processes.
 Everything even synapses are in superposition. State
reduction is happening inside consciousness.
 Intent can cause changes in the structure of the brain that
can ultimately affect behavior.
 Consciousness is not directly involved but intentions !!!
collapse the superposition.
Henry Stapp Views
 Intention effectively determining the trend of
events.
 This is experimentally verifiable. Physical effects
far away and instantaneously... (entanglement)
 Is intention a separate agent?
 Is non-locality acceptable to you?
QBism
 There is no superposition.
 We can’t remove scientist from science.
 The subjective experience is our only link with the
external world.
 Wave-functions are not real. They are abstractions
that help us to organize our thinking.
 One takes the wave function to be associated with
a physical system —based on past experience, then
calculates the likelihood of what might come next.
QBists
 quantum non-locality is the belief that an action in
one region of space can instantly alter the real state
of affairs in a faraway region.
 Therefore the wave function is only one’s
expectations.
 The only change is in the expectations of the
perceiving person.
QBists
 Most physicists don't like to recognize the
experimenter’s effect in scientific experiments.
They take science as strictly objective and real. Do
you ?
Is experimenter part or apart from experiment
result?
Whom do you believe?
 When experts are in disagreement, you can choose
the expert or speculate on your own.
 A point to take home is,
There are so many unknowns. However, bizarre things
maybe happening which is beyond or current logic and
understanding
Food for Thought
 Solving the enigma requires a multi disciplinary
approach.
 The act of observation is best studied in coordination
with neurophysiology and psychology. It is beyond
physics discipline alone.
Reductionist Pyramid
Free Will
In the double slit experiment, we can choose to see
interference or a band.
In the entanglement experiment, we choose the polarization
axis of a far away particle.
Are we robots?
Are we governed by the neurochemistry of
our brain?
Free Will
Are we governed by the quantum potential?
Isn’t free will our intuition?
Determinism of classical physics denies
free will. Uncertainty of QM allows it.
But QM randomness denies it again.
WHO IS Observer?
 Any material detector?
 Any living organism?
 Just human beings?
 How about other life forms?
 Does any species have its own reality?
Can Physics solve the Observer
problem?
 Physics is studying subjects which are
simple, well defined and testable.
 When it comes to atoms and molecules,
chemistry comes to the picture,
 Function of more complex structures such
as organisms belong to biology.
Interconnected or Separate?
 in QM objects are not separate.
 Since everything encountered everything else
sometime in the past, all component of the universe
are interconnected!!
 Therefore, what happens to one upon observation
influences all of the particles in the universe.
Physics or philosophy
 Einstein rejected the idea that observer creates reality.
 most physicists prefer to just look at the experiment.
They prefer to ignore the Skelton in the closet.
 some theorists just touch the surface.
 Many times the profound interpretations are left to
philosophers.
Emergence of a classical world
 Appearing one observable state for sub-atomic
particles is easy. How do they inter-relate and create a
logical world that we perceive is the question.
 How does an almost logical and in order classical
world emerge from quantum frenzy?
Wigner’s friend
a thought experiment
 It posits a friend of Wigner who performs the Schrödinger's
cat experiment after Wigner leaves the laboratory. Only when he
returns Wigner learns whether the cat is alive or dead.
 Is the state of the system a superposition of "dead cat/sad friend"
and "live cat/happy friend," only determined when Wigner
learned the result of the experiment, or was it determined at
some previous point?
 It illustrate that consciousness is necessary to the quantum
mechanical measurement process. In case of a detector , the
linearity of the wave function implies that the state of the system
is in a linear sum of possible states. It is simply a larger
indeterminate system.
A conscious observer must be in either one state or the other,
hence consciousness is not material in origin.