Thus, in discussing anything related to time, fundamental physics, or presence, it will be to helpful to first define a few very different types of presence.
For simplicity, the following definitions use the assumption that fundamental physical reality is 4D, which is a facet shared by classical physics, Newtonian physics, and Einsteinian physics. Needless to say, the definitions could easily be modified to work equally with more or less dimensions of spacetime. In that way, I am not claiming that reality necessarily is 4D, versus 2D or 11D or whatever, but rather just using 4D reality as an example.
Types of Presence
- Geometric Temporal Point: An imaginary 0D point on a 1D line of preconceived time; commonly colloquially referred to as "a point in time"
- Universal Temporal Presence: A multidimensional spacial frame of objectively simultaneous events corresponding to a universal objectively current "point in time", which in 4D physics means that it is vast and all-encompassing in three spacial dimensions but infinitesimal, near-infinitesimal, and/or point-like in one temporal dimension; often referred to as a "Universal Now"
- Spacial Presence: Here-ness; a 0D point in 3D space, generally treated as the metaphysically special single origin point--i..e where X, Y, and Z all equal 0--for all mathematical and geometric purposes; colloquially it tends to be ill-defined such that it often arbitrarily includes a small multidimensional blob arbitrarily near the imaginary 0D point in space, such that someone might say, "these papers are over here in space, but those papers are over there in space," all relative to a certain imaginary reference point in space.
- Temporal Presence: Now-ness in time; a 0D point in time, metaphysically distinguished from all other points in time somehow such that it is conceived as the origin point (i.e. where T=0) for all mathematical and geometric calculations. It's the same as here-ness in space but in preconceived time instead of preconceived space. Colloquially, one may use words like soon instead of near to describe the same abstract geometric concept.
- Spacetime Presence: Here-and-now-ness in timeless spaceless spacetime (an imaginary 0D point in 4D spacetime).
- Conscious Presence: An equivocal ill-defined concept that either refers to consciousness itself or to something that requires consciousness and emerges from consciousness. It's similar to reports of conscious free-will in that it is ill-defined but often appears to refer to something that transcends sharable science. It is linked to if not defined by the reported sense that each human has at every point in their waking lives that at that point they are at the center of the 4D universe, both in time and space and in all of 4D spacetime, in some allegedly true non-illusionary way, which seems to violate the Copernican Principle. However, until if ever there is a resolution to The Hard Problem of Consciousness, this concept remains ill-defined and would presumably have to be considered to transcend all current science and scientifically known physics.
In this topic, I do not wish to discuss "conscious presence". In the context of this topic, I am not claiming that "conscious presence" (whatever that means) exists or doesn't exist. I'd quicker discuss the existence of Russell's Teapot or the proverbial tree that fell in an unobserved forest. In this topic, I do not intend to resolve or discuss the Observer Problem in physics, nor resolve The Hard Problem of Consciousness which is a problem that plagues both philosophy and physics.
Rather, my primary thesis is that all the above forms of presence, except for the ill-defined "conscious presence", do not really exist.
In other words, my thesis in this topic is that all forms of unconscious presence do not really exist.
In yet other words, without consciousness, the universe has no now or present in any of the above senses. For instance, it does not have a presence in time (i.e. a now in time); it does not have a presence in space (i.e. a here in space); and it does not have a spacetime presence (a here-and-now in timeless 4D spacetime).
Thus, any conception of the universe is fictional that involves the use of a special center or origin point, meaning a special point where objectively X=0, Y=0, Z=0, and T=0, which are basically just mathematical ways of saying here and now, or here-and-now.
However, because Einstein showed that space-ness and time-ness are relative (in part to each being relative to that origin point and a corresponding reference frame among other conceptual relativistic modeling constructs), that means that space and time are fictions too. In that way, space and time are like the X axis and the Y axis. Space and time are arbitrary fictional constructs that can be included in certain types of made-up reference frames to geometrically or mathematically model a fictional version of the universe. What is a dimension of space in one reference frame can be a dimension of time in another. Each reference frame treats its origin point as the center of the relativistic block universe (where X=0, Y=0, Z=0, and T=0), but neither such a center nor the reference frame actually exist. They are fictional constructs intentionally designed to create a fictional model of the universe.
Similar to denying free will, denying time or presence in any way can come across as counter-intuitive and possibly laughable to many people, even though the objections may at best border on the mystical and supernatural if not the utterly illogical. Even in 2021 on Earth, there are some people scattered on the globe (pun intended) who are convinced that Flat Earth Theory is true. They would laugh at the idea of the Earth being round.
To help sneak past the fallible laughter test, I will break down each crucial sentence of my position by number so that respondents can easily point to which statements they find objectionable versus agreeable.
However, one last note before I make my sneaky attempt to slide through the defenses of the laughter test. For the purposes of the following statements, for simplicity, by "really exist", I mean in the strict physical sense of actual fundamental reality and/or fundamental physics. This is the same sense in which Santa Claus does not really exist, even though the concept of Santa Claus does exist, and even though in relativistic contexts we might say it's true Santa lives at the North Pole, and false that Santa lives at the South Pole, even though really there is no Santa, and thus, in terms of actual fundamental reality, the concept of where Santa lives is incoherent nonsense. Asking me when or where something exists may be like asking me where Santa lives, in that I can answer but only by assuming useful falsehoods. In actual reality, there is no Santa, there is no where, and there is no when.
With that important last note about the strict fundamental context of what I mean by "really exist", I hereby give you my argument against presence and time:
 A 0D point is a mathematical construct.
 0D points do not really exist.
 A 1D line is a mathematical construct.
 1D lines do not really exist.
 The X-axis and Y-axis are each both mathematical constructs.
 X-axis-ness and Y-axis-ness do not really exist.
Example: If we have three different people draw a 2D graph to represent the location of pool balls on a specific pool table, and then ask each person whether or not the red ball is on the right side of the Y-axis, with such right-side-ness corresponding to positive values for X (i.e. X > 0), each person may give a different answer depending on how they graphed it. In that way, we can say that each X-axis and Y-axis is conceptually relative to the graphing process. The 2D surface of the pool table does actually have an X-axis or a Y-axis, and likewise thus doesn't have real leftness or rightness.
 Leftness and rightness do not really exist.
Example: It would be meaningless to ask if Mars is on the left side of the universe or the right side of the universe. Those concepts only have meaning in fictional contexts relative to arbitrary mathematical metaphysical fictions. For instance, one needs to first conceive of a fictional geometric model with an arbitrary fictional origin point and an arbitrary fictional axis (e.g. a Y-axis) with which to relativistically distinguish things as left of that fictional axis or right of that fictional axis. Thus, the relativity of left and right isn't merely a matter of relations between real things (e.g. one pool ball versus another ball), which is a lesser form of relativity, but more deeply than that they are also relative to fictional mathematical constructs such as an imaginary conceived axis and orientation, conceptually projected or imagined in some way. Asking if something is left or right is like asking if Santa gained weight recently, or if he is generous with his gift-giving on Christmas; strictly speaking; it is incoherent and meaningless because such ideas are relative to fictions that vary.
If this item (#7) is the first with which you disagree, please post reply in both of these other two topics instead of this one: Objective Leftness and Rightness Do Not Exist and Would Flat-Land Four-Eyed Freddy Notice a Difference?
 Up-ness and down-ness do not really exist.
Example: It would be meaningless and incoherent to ask if Pluto is above the center of the universe or below the center of the universe. This is because like the X-axis on a pool table, the so-called center line to which it is relative is a fiction. It's not just fictional because the physics happen to be relative, but rather the physics are so relative because it's a fiction. When we ask how far a pool ball is from the X-axis, we are relating it to something the doesn't exist. in this case the X-axis and by extension x-axis-ness.
 Vertical-ness and horzional-ness do not really exist.
Example: Between graphs of the same pool table, what is leftness on one graph can be upness on another graph. So it's not just left and right that are relative to each other, but the concept of left-right-ness and up-down-ness are relative with each other. One person could say the ball moved 2 centimeters to the left, but another person would say the same ball moved 2 centimeters up, and yet another graph would indicate it moved 2 centimeters diagonally equally on the X-axis and the Y-axis.
 A universal line of vertical-ness does not really exist.
 An objective line of vertical-ness does not really exist.
 A single relative line of vertical-ness does not really exist.
Clarification: We could say that infinite possible relative lines (plural) of vertical-ness exist, but that is like saying that many possible variations of Santa Claus exist, or that many translations of Alice in Wonderland Exist. We can say that multiple fictions exist, but strictly speaking none of them really exist, in terms of fundamental reality and the fundamental physics. The fact that infinite equally true alternative but contradictory stories exist is a symptom of fiction.
 Flat Earth Theory is wrong and debunked.
Clarification: One can still use useful oversimplified models in narrow contexts to get useful results, such as using a flat 2D map on flat paper to go on a hike. In another example, an engineer designing a bridge can just falsely assume that gravity is pulling straight down in all directions for simplicity, even though that's not compatible with a center gravity at the center of a globe.
 Newtonian Mechanics are wrong and debunked.
Clarification: One can still use useful oversimplified models in narrow contexts to get useful results. For example, if timing swimmers at the Olympics, the humans holding stop-watches can all do their work using oversimplified false classical mechanics, rather than requiring all humans timing the race to solve Einstein's field equations before a winner can be declared.
] Simultaneity is not objective, but rather relative to fictional reference frames.
Example: From one reference frame, A can precede B, and B can precede C; but from another reference frame B may occur first, and then A, and then C.
 Objective space does not really exist.
 Objective time does not really exist.
 Time is fundamentally and metaphysically indistinguishable from space in essentially the same way that left is fundamentally and metaphysically indistinguishable from right.
 Time is fundamentally and metaphysically indistinguishable from space in essentially the same way that x-axis-ness is fundamentally and metaphysically indistinguishable from y-axis-ness.
Clarification: Time is time only according to and relative to a given fictional graphing or given fictional conceptual reference frame; on a different reference frame the so-called time would then instead be space, or would be a mixture of space and time. Neither the reference frame nor up-ness, down-less, forward-ness, backwards-ness, or time-ness actually exist.
 Forward-ness in space and backward-ness in space do not really exist.
 Future-ness and past-ness do not really exist.
 In terms of their non-existence in physical reality, the future and the past are like up and down, left and right, front and back.
 There is no objective here.
 There is no objective now.
 There is no objective here-ness.
 There is no objective now-ness.
 There is no objective space-ness.
 There is no objective time-ness.
 For Special and General Reactivity to be valid and work, 4D spacetime cannot be and is not 3Ds of space plus 1D of time, but rather 4 fundamentally equal dimensions of timeless spaceless spacetime.
 None of the 4 dimensions of 4D spacetime is fundamentally special or different in any real objective way, meaning there is no fundamental way to objectively categorize 3 of the 4 dimensions together as being more alike than the others.
 In classical or Newtonian mechanics it may be a choice or matter of interpretation to use a block universe model instead of a non-block universe model, but in Special Relativity it is no longer a choice or matter of interpretation. Einstein's physics do not work without the relativity of space-ness and time-ness, rendering them as arbitrary as x-axis-ness and y-axis-ness.
 The universe has no X-axis or line of X-axis-ness.
 The universe has no axis of time or timeline.
 Anything that is a past event relative to one reference frame is a future event to infinite other reference frames.
 Anything that is a future event relative to one reference frame is a past event to infinite other reference frames.
 Your past is someone else's future.
 Your future is someone else's past.
 The 4D block universe contains everything that really exists physically in 4D spacetime, regardless of whether it would be considered past or future from any given reference frame.
Clarifications: In other words, roughly speaking, the 4D block universe contains everything you would consider past or future.
 The 4D block universe contains the Big Bang, real dinosaurs, all humans who have ever lived, the death of the Sun and everything else that physically exists.
 The 4D block universe has no real singular presence such that it is impossible to say that certain events (e.g. the death of the Sun or the Big Bang) exist objectively in the past or the future.
 All so-called events (e.g. the death of the Sun or the Big Bang) all exist together in the block universe, which has no present, no future, and no past, but rather is eternal and timeless.
 Objectively speaking, no part of the block universe is the past part and no part of it is the future part.
 There is no animated 'present' acting as a moving border between the past and the future because the past and the future do not objectively exist in the same way that right and left do not objectively exist.
 Assuming there is nothing transcendental to the 4D block universe, without objective time, change is incompatible with determinism.
Example: If the Big Bang and the death of the Sun are changing or could change, then determinism is not true.
 Causal determinism is true, at least in regard to everything that can be scientifically said to physically exist within the 4D block universe of timeless spacetime.
Clarification: If there are things transcendental to the unchanging 4D block universe (e.g. transcendental consciousnesses, plural), then those transcendental things could all each have their own changing relationship with the unchanging block universe, and the mechanics of those transcendental interactions could be deterministic or not. Because it's transcendental, it would presumably be scientifically immeasurable and physically unobservable, at least in any standard third-party way that doesn't result in a form of the Observer Problem.
 Without something transcendental to the 4D physical world and everything contained within the entirety of 4D spacetime, there is no change, and thus any alleged change is not real.
 The 4D block universe that contains everything in 4D spacetime is timeless, unchanging, and eternal.
 All humans including Oscar Wilde and Britney Spears timelessly eternally live in the unchanging 4D block universe of timeless 4D spacetime.
If you disagree with any of the above statements, please explicitly specify which one(s) and why.
Important Clarification about Consciousness
None of the above statements necessarily apply if one is speaking in relation to consciousness(es), some conscious present(s), or conscious observer(s), all of which could possibly be claimed to be some kind of real subjective/pseudo-objective thing(s) acting like reference point(s), but real, instead of fictional. It's very different to talk about something that's relative to some alleged consciousness(es) (presumably plural) than relative merely to a fictional made-up reference point in spacetime. In other words, there is a big difference between a fictional reference frame versus an alleged conscious experience that itself--if it exists--might favor or better correspond to a certain kind of reference frame, even though in practice the two often get falsely and confusingly conflated.
If a special form of relative emergent timelines emerge from the alleged existence of conscious presents, then presumably there is either 0 of those timelines, or there is infinite such emergent timelines, that is unless solipsism is true. If solipsism is true, then and only then could a single emergent relative timeline be logically said to exist.
The belief or consideration of such vague propositions of conscious presences would open Pandora's Box, so to speak, by raising all kinds of countless presumably unanswerable questions, such as but not at all limited to whether the "conscious presences" are each 0D like a reference point and to what degree do the "conscious presences" transcend the unchanging 4D block universe that includes all of spacetime. Anyone attempting to answer such questions might be wise to first register their religion as tax-exempt with the appropriate government authorities, if not just for the financial savings.