The physical world deteriorates, because of the Chet of the Etz Hadas, the sin of Adam, and the golden calf, etc.
Sin disconnects one from Hashem; and since all life comes from Hashem, this disconnection results, in a lessening of the life of Hashem into the person, and into the world at large.
Adam was supposed to have lived forever, but because of his sin, his life-span was shortened to nine-hundred and thirty years. And because of the continual sinning of every generation after Adam, the life-span was continually shortened.
This continued until after the sin of the golden calf, when the life-span became much shorter (my example).
One or two generations ago, people lived only forty or fifty years, but in our times people live seventy or eighty years.
We see, that as we get closer to the revelation of Moshiach, people’s life span has continually increased; until now it is becoming more and more common for people to live over one hundred years.
And scientists are now researching methods that they say, may be able to help people live much, much longer.
This is because, as time goes on the world becomes more refined. Meaning, that it becomes more and more reconnected with Hashem, the source of life; and the coarseness that was brought to world by the sin has been gradually removed.
Galus can be compared to a radio. If a radio (the creation) is not plugged into its source (Hashem), then it just a worthless piece of plastic (it deteriorates); but on the other hand, when it is plugged into its source, it becomes alive.