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Theory Group Lunchtime Seminars

Scheduled seminars are listed below.

Announcements and reminders will be posted to the physics_theory_group_seminar list. Click here to subscribe.

[If you are a member of the group, you will receive postings to this list via physics-theory or physics-theory-staff. You do NOT need to subscribe to the above mailing list.]


 
 
Thu 23 Jan, '20
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Theory Seminar: Simone Sturniolo (STFC), The road not taken: quantum mechanics without a wavefunction
PS1.28

The most common interpretation of quantum mechanics has it describe the world in terms of wavefunctions and probabilities, replacing pure classical determinism. Yet when the Schrödinger equation was first introduced, its meaning was not obvious. Already in 1927, Louis deBroglie suggested a different interpretation of it than the one we know, a deterministic approach in which the wavefunction is merely ‘piloting’ the true particle, which is a classical entity obeying however to weird, unfamiliar laws of motion. This approach was then developed further by David Bohm in the 1950s, thus becoming known as ‘Bohmian mechanics’. While it never gained mainstream popularity, it occasionally provided fertile ground for new developments, such as Bell’s work on the restrictions to hidden variable theories.

In this lecture we will present the fundamentals of Bohmian mechanics as well as the Many Interacting World approach, a new reformulation of it proposed in 2014 that does away with the wavefunction altogether. We will see how these theories recast the same phenomena we’re familiar with in a new light, how they can be useful to gain a deeper understanding of quantum behaviour by visualising it in classical terms, and finally how they can be applied to the field of computational physics, where simplifying assumptions make it a potentially useful method to deal with the problem of quantum effects involving atomic nuclei in matter.  

Thu 6 Feb, '20
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Mark Hadley, Physics and Free Will
PS1.28

The relationship between free will and scientific theories is a century old unresolved problem endlessly debated by philosophers. Claims are made of a crucial role for quantum theory. That's fascinating but unconvincing . By taking a novel scientific approach, I have developed the challenge model which is a testable solution to the problem.

Thu 13 Feb, '20
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Theory Seminar: Patrick Pietzonka (Cambridge), Thermodynamic bounds on currents in driven and active systems
PS1.28

For fluctuating thermodynamic currents in non-equilibrium steady states, the thermodynamic uncertainty relation expresses a fundamental

trade-off between precision, i.e. small fluctuations, and dissipation. I will review generalisations and implications of this

relation, including bounds on large deviation functions and applications to molecular motors and heat engines.

The second part of my talk will be concerned with the thermodynamics of active matter systems, which can drive engines that autonomously

deliver mechanical work against an external mechanical force. We explore design principles for such engines and compare their power and

efficiency to idealised work extraction mechanisms. A mean field approach reveals that the interaction with the passive particle can

mediate cooperativity between otherwise non-interacting active particles, leading to an enhanced efficiency.

Thu 20 Feb, '20
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Theory Seminar: Dmitrii Kolotkov (Warwick)
PS1.28

tba

Thu 27 Feb, '20
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Theory Seminar: Sofia Qvarfort (UCL), Detecting gravitational effects with optomechanical systems
PS1.28

tba

Thu 5 Mar, '20
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Theory Seminar: Joseph Betouras (Loughborough)
PS1.28

tba

Thu 12 Mar, '20
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Theory Seminar: Hatef Sadeghi (Warwick)
PS1.28

tba

Thu 11 Jun, '20
TCM 2020