Results 51 to 60 of about 68,867 (287)
Based on the square heat-generation body (HGB) with “arrow-shaped” high-thermal-conductivity channel (HTCC) model established in the previous literature, we performed multi-objective optimization (MOO) with maximum temperature difference (MTD ...
Hongwei Zhu+4 more
doaj +1 more source
Fluctuation, Dissipation and the Arrow of Time [PDF]
The recent development of the theory of fluctuation relations has led to new insights into the ever-lasting question of how irreversible behavior emerges from time-reversal symmetric microscopic dynamics.
Bochkov+6 more
core +6 more sources
Cosmological Time, Entropy and Infinity
Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motion and on the strength of the gravitational ...
Clémentine Hauret+2 more
doaj +1 more source
Where was the past low-entropy of the early universe located? Contrary to some popular answers, I argue that that the dominant source of low-entropy is the fact that a single degree of freedom, the scale factor, was not at equilibrium.
Carlo Rovelli
doaj +1 more source
Vacuum structure for expanding geometry [PDF]
We consider gravitational wave modes in the FRW metrics in a de Sitter phase and show that the state space splits into many unitarily inequivalent representations of the canonical commutation relations.
Albrecht A+33 more
core +3 more sources
Arrow of time across five centuries of classical music [PDF]
The concept of time series irreversibility -- the degree by which the statistics of signals are not invariant under time reversal -- naturally appears in non-equilibrium physics in stationary systems which operate away from equilibrium and produce ...
Alfredo González-Espinoza+2 more
semanticscholar +1 more source
Deflation at Turnaround for Oscillatory Cosmology [PDF]
It is suggested that dark energy in a brane world can help reconcile an infinitely cyclic cosmology with the second law of thermodynamics. A cyclic cosmology is described, in which dark energy with constant equation of state leads to a turnaround at ...
Baum, Lauris, Frampton, Paul H.
core +5 more sources
Black-Hole Uncertainty Entails an Intrinsic Time Arrow. a Note on the Hawking-Penrose Controversy [PDF]
Any theory that states that the basic laws of physics are time-symmetric must be strictly deterministic. Only determinism enables time reversal of entropy increase. A contradiction therefore arises between two statements of Hawking.
't Hooft+21 more
core +4 more sources
The Decoherent Arrow of Time and the Entanglement Past Hypothesis [PDF]
If an asymmetry in time does not arise from the fundamental dynamical laws of physics, it may be found in special boundary conditions. The argument normally goes that since thermodynamic entropy in the past is lower than in the future according to the ...
Jim Al-Khalili, Eddy Keming Chen
semanticscholar +1 more source
Comment on `Quantum resolution to the arrow of time dilemma' [PDF]
Recently, a substantial amount of debate has grown up around a proposed quantum resolution to the `arrow of time dilemma' that is based on the role of classical memory records of entropy-decreasing events.
Jennings, David, Rudolph, Terry
core +2 more sources