Time is relative to the matter experiencing an expanse and duration thereof. If you are a piece of carbon-steel then your time in the form of that said metal, your time is relative in comparative relevance to a human's time here on earth. The piece of metal will last longer than the individual human. Your matter is relative to entropy, or how long the atoms in your body are going to remain in the form of a human. What is the substance-matter of life? If you were to remove; the carbon, water, and other various vitamins and minerals, What substance would remain? Is that substance relative to the behavior of the person prior to the removal of their body of matter?
The only reason time exist is because all life on earth will only get a certain amount, or measurement of "time." "Are we there yet, mom?" She replies, "NO. We will get there when we get there!" This is true of human-time here on earth. We will not know now much we will get until we pass to places yet know to mankind. The amount of time that a person receives can also be relative to their behavior. If you use drugs and/or alcohol your life might not be as long as the person whom does NOT ingest those types of atoms. Is entropy different for life than it is for pure substances that do not contain a spirit?
There is not an answer that I'm comfortable with presenting at this juncture. This is largely due to the fact that I have not experienced death in the past. We are not going to discuss that now-we being; me, myself, and I. I know there is no, "I" in the word team. Maybe that is why us humans get less time than a rock sitting, wherever you can see a rock, because humans get the luxury of being able to have our; body, mind, and soul, work as a team. Some people are better at team-work skills than others but that is could be relative to effort and effectiveness not the substance-matter that is your body. Unless there are extenuating circumstances, like a bum-leg or a mental disability.
Science has argued that each form of matter has it's own rate of entropy(the second law of thermodynamics). That being, that matter will deteriorate at a predictable rate based on the frequency of the atoms vibration and temperature. This is a somewhat incomplete explanation of entropy. However it will work well enough for "it" to be relatively useful. Carbon-Dating uses the theories of this law to gather an estimated length of time that a particular piece of matter has been on the face of the earth or within the universe. Like a carbon-dating: entropy gives us a general measurement of how long an atom or system of molecules will remain in order that we are presented with. The atoms and molecules will go from a state of order to a state of disorder at a rate determined by the atom and how atom relates to it surroundings.
Time is relative to living things, because we only get so much time on earth and our behavior can determine how much of this measurement we will receive while walking in these human-soul-shoes. Some people believe that money is relative to happiness. What if acceptance was relative to to satisfaction? Would
you accept more or less? And of what substance? These question's answers are relative to the person you you ask them of? Just like time is relative to the matter experiencing that particular segment of existence. Are we there yet? You tell me! Because I might not have the answer you may be willing to accept as your own terms of relative existence. It sure can be confusing, but in real time your own acceptance will come to you in a relative short amount of time.