Sounds like a joke thread to me. All life is macroscopic in nature - even viruses and bacteria. No living thing exists on the Plank scale. An observation, in the sense of quantum mechanics occurs on the size scale were quantum mechanics dominates. To influence a quantum state, you must observe on the quantum scale. At our large scale, quantum effects blurr into the classical laws of physics. This is the decoherence mentioned in the article.
This is the part of the articel I have trouble with: Physicists agree that the macroscopic or classical world (which seems to have a single, 'objective' state) emerges from the quantum world of many possible states through a phenomenon called decoherence, according to which interactions between the quantum states of the system of interest and its environment serve to 'collapse' those states into a single outcome. But this process of decoherence still isn't fully understood.
I always thought that the quantum states were properties associated with materials invovled. For example, the green in the leaves of a tree arise from the absorption of light of a frequency whose energy matches the quantum transition from a ground state to an excited state in chlorophyll. One molecule of chlorophyll is like every other and has the same transition state. The only change would be slight variations in its chemical environent that can casue the energy for the transition to shift slightly higher or lower, hence casuing a broadening of the wavelength window responsible for the observed color. I don't see where the authors see a continuum of states and some are selected on a macroscopic scale when the quantum effects are entirely macroscopic and the possible states are determined before even reaching the classical domain.
It is physically impossible even for two macroscopic observers to see the exact same thing. For example, if two people were looking at a flower, each person sees something different. Different photons of light reach the different people. No two people detect the same photon or the same transition.
All right, I'll bite, I don't mind.
What about when the light is acting like a wave?
Rayleigh, Jeans
had not the means
Einstein didn't want 'em
It took Neils Bohr
and several more
to figure out the quantum...
(Hazy quote from memory, from (I believe) an old article in Physics Today...)
Cheers and Merry Christmas!
Chlorophyll is a molecule containing many atoms which all have different "excitation states" available to emit (reflect) light. Thus, all light is absorbed and many wavelenghts (mainly in the green spectrum) are emitted.
One molecule of chlorophyll is like every other and has the same transition state.
Actually, there oare two types of chlorophyll molecules but that is beside the point. There are many transistion states with those with energies corresponding to the greens emitting while the other frequencies of light are not (at least for the most part) emitted but the absorbed energy (exitation) is converted into molecular re-actions.
The only change would be slight variations in its chemical environent that can casue the energy for the transition to shift slightly higher or lower, hence casuing a broadening of the wavelength window responsible for the observed color.
Again, it is a molecule and has many transition states resulting in many frequencies being emitted (reflected). You are partially correct in that bringing atoms and/or molecules in close proximity results in additional transition states (frequencies).