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Les Sleeth
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I am thinking mostly about all that heat released in stellar activity, but any insights about this might help resolve a little debate I'm having with a friend.
The Bob said:I would say that Mass is Energy, therefore, the universe is not losing mass because to lose energy is to destroy it and that is not possible. Therefore the universe is not losing mass.
selfAdjoint said:Mass can, under certain conditions, be converted to energy. Energy can, under certain other conditions, be converted into mass. When none of these conditions apply, they are different.
I would think so. It is true that mass/energy total will remain the same, but mass and energy are just two forms of "an entity". We could have all matter and no energy or all energy and no matter, but either is unlikely.Les Sleeth said:Dare I ask? Under the current conditions in our universe, is it proper to say that mass is being converted to energy at a higher rate than the reverse, and therefore overall mass is becoming less available (than it used to be) for . . . ?
True. My post would have been more appropriate if the question would have said matter/energy instead of mass/energy...Chronos said:The equivalancy principle makes no distinction between mass and energy, energy is just more diffuse. In GR, they are treated as the same.
Are we losing both mass and energy as galaxies disappear behind the cosmological event horizon? IIRC we do not see anything in our present light cone disappearing behind the cosmological event horizon. But we are looking into the past at distant galaxies. Yet what about the event horizon as it exist today. Though we may not see it yet, are distant galaxies leaving our field of vision and influence due to the expansion of the universe? Thanks.Les Sleeth said:Dare I ask? Under the current conditions in our universe, is it proper to say that mass is being converted to energy at a higher rate than the reverse, and therefore overall mass is becoming less available (than it used to be) for . . . ?
Labguy said:True. My post would have been more appropriate if the question would have said matter/energy instead of mass/energy...
But, Hawking wrote that there is no "real" meaning for the word mass other than simply "a quantity of matter". I wonder if we could also say "a quantity of energy"? Doesn't sound right that way, somehow.
From Sleeth's second post, second paragraph, it actually sounds as if he is meaning "matter" instead of mass. The burning wood example, for instance. (?)
Since you said "tied up in a particle" it appears you mean matter (particles) vs energy (=mass). If that is the case, then I would think that all the answers posted above are correct. Some about mass, some about matter, but the bottom line is entropy.That's what I meant by asking that, if there is no difference between energy tied up in a particle and that which appears to have been set free to disperse forever,...
Ok,...,but; to what above does this statement apply??Chronos said:Heat makes particles move. Kinetic energy is the lowest form of energy. Energy is not lost because particles gain momentum from it. They subsequently transfer that momentum to other particles with which they collide.
Chronos said:Heat loss. Heat energy is radiated [in the infrared spectrum] until it is imparted to a massive particle causing it to move, or kick an electron into a higher energy state. Eventually it is all translated into kinetic energy.
The mass of the Universe is a difficult concept to measure, as it is constantly changing and expanding. However, scientists estimate that the observable Universe has a mass of approximately 3 x 10^55 kilograms.
Scientists use a variety of methods to measure the mass of the Universe, including studying the movements of galaxies, observing the cosmic microwave background, and analyzing the distribution of matter. These methods have shown that the Universe is indeed losing mass, mainly due to the expansion of space.
The main cause of the Universe's mass loss is the expansion of space. This expansion, which has been observed since the early 20th century, is causing galaxies and other celestial objects to move away from each other at an increasing rate. As space expands, the density of matter decreases, resulting in a loss of mass.
The exact amount of mass that the Universe loses per year is difficult to determine, as it depends on various factors such as the rate of expansion and the amount of dark matter present. However, estimates suggest that the Universe may be losing around 0.0000000000000000000000000000000000000000000000000000000000000000000000000000001% of its mass per year.
Based on current observations and theories, it is unlikely that the Universe will run out of mass. While the expansion of space may continue to cause a loss of mass, the amount of dark matter and energy in the Universe is thought to be more than enough to keep the Universe from running out of mass. Additionally, new matter is constantly being created through processes such as stellar fusion and particle collisions.