rationalskepticism.org

Oldskeptic wrote:
It is heat loss from the surrounding environment, and the surrounding environment of new empty space is previously existing empty space. The universe began at 10^29 degrees Kelvin. The ambient temperature of the universe today is 2.76 Kelvin. Where do you think that all of that energy in the form of heat went? With no surrounding environment, because the universe is an isolated system, for this heat to wick away, what would be your explanation? Mine is that with every cubic centimeter of space created by expansion it becomes more spread out and so diluted and empty space gets cooler as expansion increases.

AMR wrote:
But with only 2.76 K of blackbody radiation left to dissipate why is the universe's increasing expansion accelerating now and into the future? If there is less heat left to radiate wouldn't the rate of expansion slow?

Your question would make sense if the dissipation of heat was what was driving expansion, but it is not. The dilution of thermal energy is a result of expansion not the cause. Even when or if a time is reached where all matter has decayed giving up its potential thermal energy and all thermal energy has dissipated to the point where maximum entropy is reached again, but in a different form, the expansion may not stop nor slow down. Dark energy according to the hypotheses does not on act anything other than “empty” space.

You want an outside energy source that drives expansion, but you can’t have it. Not anymore than you can have an outside energy source that drives gravitation. Gravity “pulls” matter towards matter, it has positive pressure, and the closer things get to each other the stronger the mutual attraction. The force of gravity does not increase as distance diminishes but the strength of attraction does. We see the same accelerated behavior in one body “falling” towards another body with gravity as we do with expansion. A closing of distance at faster and faster rates the shorter the distances get.

Gravity is an attractive force with positive pressure. Dark energy or the effect of it can be seen as a repulsive force with negative pressure. Gravity has a strong affect on matter but a very weak affect on empty space- Dark energy has a strong affect on empty space but no, or a very weak affect, on matter.

There is no need for an outside input of energy to drive accelerated expansion if it follows the same rules as accelerated attraction that gravity does.

It appears that gravity and dark energy may be flip sides of the same coin, and evidence for this is that the universe was not always undergoing accelerated expansion. But some crucial point in the size of the universe and the amount of empty space was reached where the volume of empty space and its connected repulsive force became large enough to be strong enough to overcome gravity and begin speeding up instead of slowing down expansion.

Now we come to the cosmological constant. Einstein’s cosmological constant was strong enough to allow for, even promote, initial expansion but weak enough to allow gravity to restrain expansion when equilibrium was reached between the attractive force and the repulsive force. Einstein was wrong in the value, but correct in the concept.

Oldskeptic wrote:
I will have to point out that at the instant of the “Big Bang” entropy plunged to a minimum state and has been increasing overall since then. Why? Heat loss which causes increasing entropy, and follows the 2nd law.

AMR wrote:
So you are saying that the 2nd Law of Thermodynamics is invalid since it goes automatically from maximum to minimum entropy?

Not at all , the 2nd law always applied both before and after. In the singularity there was no heat loss to a surrounding environment because there was no surrounding environment, and being pure plasma no part was distinguishable from any other. This is called rotational symmetry. A perfect sphere has rotational symmetry of 1/1. It is at maximum entropy if there is no heat loss. A circle has a rotational symmetry of 1/2. A square 1/4 . And a snowflake a1/6

Even though the proto-universe was extremely hot its density and gravity could keep it in a state of maximum entropy. But there is something called spontaneous symmetry breaking. Once this occurred and expansion began, heat loss began.

Heat loss to surrounding environment is part of the 2nd law, but so is heat loss to expanding environment, so with the temperature of the universe going from maximum towards a future minimum in an instant the expanding universe went from maximum entropy to minimum entropy just that fast.

Also at the instance of initiation of expansion, particulars (Not particles because at this extreme heat physical particles are not possible) that made up the proto-universe began flying off in different directions. Symmetry was a thing of the past, and symmetry is key to and required by maximum entropy.

If you want to talk about the 1st law or the 2nd law or entropy then you should try to gain an understanding of them. Especially if you want to question or dispute them or use them in your arguments.