Quantum Phenomena and Biology · Quantum phenomena Superposition of collective electronic states? Inelastic electron tunnelling? Quantum correlated radical-pairs? Relating quantum

A L E X A N D R A O L A Y A - C A S T R O

D E P A R T M E N T O F P H Y S I C S A N D A S T R O N O M Y

U N I V E R S I T Y C O L L E G E L O N D O N

Quantum Phenomena and Biology

Bogota 15 May 2013

FACT OR FICTION?

“Quantum biology is a speculative and interdisciplinary field that seeks to link quantum

physics and the life sciences”

Quantum phenomena and Biology Alexandra Olaya-Castro

http://www.energetic-medicine.net/quantum-biology.html

FACT OR FICTION?

“Quantum biology is a speculative and interdisciplinary field that seeks to link quantum

physics and the life sciences”


Quantum in Biology:

Physics of biomolecules and the relevance of these properties for biological function

biochemistry and molecular biology

meets quantitative laws of quantum physics


Figure taken from Lambert et al Nature Physics, 9 10-18 (2013)

Biological processes of interest


Biomolecules

Light-Harvesting Antenna Bacterial reaction centre

Odour receptor

Cryptochrome


nano-scale system

Quantum phenomena

Superposition of collective electronic states?

Inelastic electron tunnelling?

Quantum correlated radical-pairs?

Relating quantum phenomena to biomolecular function

cryptochrome Odor receptor LH antennae

nano-scale process Energy transport Molecular sensing Magnetic sensing


FACT OR FICTION?

“Beard-Einstein conflation is a fundamental theory underlying high-efficient energy transfer in photosynthesis”

Solar: Ian McEwan


electronic degrees of freedom

photo-induced process

environment

“Observable” system

“Measurement”

Open quantum system description


System: collective electronic excitations

Environment: pigment vibrations, protein vibrations, low-energy solvent modes, etc. Generally described as (quantum or classical) “springs”.

Measurement: linear and non-linear spectroscopy

Example: light-harvesting antenna


Protein

Pigments

Water

b+1

V

Collective electronic excitation states

X (EX) Y (EY)

Example: Two-pigments


PXX PXY

PYX PYY

PXX 0

0 PYY

Quantum regime

Classical regime

diagonal=probabilities

off-diagonal=coherencias


High-light

Low-light

B850 nm B820 nm

B800 nm

Acclimation of quantum properties

heterogeneous ab subunits

Gene expression controls some quantum properties


Courtesy of Gregory D Scholes


Evidence of quantum superpositions during dynamics


Quantum Coherence in Biology: facts, fiction and challenges Alexandra Olaya-Castro

Example: Symmetry-tuning of transfer efficiencies

F. Fassioli, A. Nazir and A.Olaya-Castr, JPCL 1, 2139 (2010)

nano-scale system

Quantum phenomena

Superposition of collective electronic states?

Inelastic electron tunnelling?

Quantum correlated radical-pairs?

Relating quantum phenomena to biomolecular function

cryptochrome Odor receptor LH antennae

nano-scale process Energy transport Molecular sensing Magnetic sensing

Scientific challenge: Does this matter for biology


Francesca Fassioli (PDRA)

Hoda Nejad (PDRA)

Ahsan Nazir (IC)

Greg Scholes (UT) James Sturgis (CNRS)

Discussions Students and postdocs

Edward O’Reilly (Ph D)

Avinash Kolli (Former PDRA)

Gracias por su atención!!


Quantum Phenomena and Biology · Quantum phenomena Superposition of collective electronic states? Inelastic electron tunnelling? Quantum correlated radical-pairs? Relating quantum

Documents