from the in-this-house-we-obey-the-laws-of-thermodynamics dept.
https://scitechdaily.com/scientists-prove-that-there-is-no-second-law-of-entanglement/
The second law of thermodynamics is widely considered one of the most universally true physical laws. It dictates that the entropy, a measure of physical disorder, of any isolated system can never decrease over time. It adds an 'arrow of time' to everyday occurrences, determining which processes are reversible and which are not. It explains why an ice cube on a hot stove will always melt and why compressed gas will always escape its container and never return when a valve is opened to the atmosphere.
Only states of equal entropy and energy can be reversibly converted from one to the other. This reversibility condition led to the discovery of thermodynamic processes such as the (idealized) Carnot cycle, which poses an upper limit to how efficiently one can convert heat into work, or the other way around, by cycling a closed system through different temperatures and pressures. Our understanding of this process underpinned the rapid economic development during the Western Industrial Revolution.
[...] Resolving this long-standing open question, research carried out by Lami (previously at the University of Ulm and currently at QuSoft and the University of Amsterdam) and Bartosz Regula (University of Tokyo) demonstrates that manipulation of entanglement is fundamentally irreversible, putting to rest any hopes of establishing a second law of entanglement. This new result relies on the construction of a particular quantum state which is very 'expensive' to create using pure entanglement. Creating this state will always result in a loss of some of this entanglement, as the invested entanglement cannot be fully recovered. As a result, it is inherently impossible to transform this state into another and back again. The existence of such states was previously unknown.
Because the approach used here does not presuppose what exact transformation protocols are used, it rules out the reversibility of entanglement in all possible settings. It applies to all protocols, assuming they don't generate new entanglement themselves. Lami explains: "Using entangling operations would be like running a distillery in which alcohol from elsewhere is secretly added to the beverage."
Journal Reference:
Lami, L., Regula, B. No second law of entanglement manipulation after all. Nat. Phys. 19, 184–189 (2023). https://doi.org/10.1038/s41567-022-01873-9
(Score: 2) by JoeMerchant on Sunday February 19, @01:56PM (2 children)
>compressed gas will always escape its container and never return when a valve is opened to the atmosphere.
Just needs a more intelligent valve to open and close at the right times, odds are the same applies to entanglement.
What if God is simply that which resets the Universe when entropy is maximized? Like a player watching a Pachinko machine resetting the balls to the top of the board.
Україна досі не є частиною Росії Слава Україні🌻 https://news.stanford.edu/2023/02/17/will-russia-ukraine-war-end
(Score: 1, Informative) by Anonymous Coward on Monday February 20, @03:33AM
My limited understanding of Maxwell's Demon is that it doesn't work for free...and the energy cost of opening and closing that valve means that the resulting system still follows the laws of thermo. For example, Hilsch tubes https://en.wikipedia.org/wiki/Vortex_tube [wikipedia.org] separate hot and cold gas molecules...but they are not efficient.
Btw, I passed college thermo but I don't use thermodynamics in my work, so most of what I learned is lost. However, their paraphrase of the three laws stuck:
1. You can't get ahead.
2. You can't even break even.
3. You can't get out of the game.
(Score: 0) by Anonymous Coward on Monday February 20, @04:21AM
That's just the Celestial Casino's employee resetting things for the next round of betting. 😉
(Score: 2) by Mojibake Tengu on Sunday February 19, @08:17PM
Quantumists still did not reinvented hyperoperations, nor the Grzegorczyk hierarchy.
Let's just wait and see...
The edge of 太玄 cannot be defined, for it is beyond every aspect of design
(Score: 0) by Anonymous Coward on Monday February 20, @01:25AM
That's why I think there's no time dimension, no past to "time travel to" (as per popular fiction). Time is just what we use to measure[1] the change in stuff. At least from the perspective of within this Universe (from outside maybe there are copies of the past made).
Like in a computer game - the characters might talk about the past, but there's no actual past to travel to (unless you saved some game states, or played the game in a VM and saved/copied the VM).
[1] But the way we choose to measure the change gives a deceptive illusion to some people that we can visit the past.