First of all, you must go outside our atmosphere because we have 10 to the 19th particles of the air density on the Earth which is exactly why you say there is space in the room. That space is full of particles filling the volume. Imagine being in the intergalactic space where density is 1 particle per 1 cubic meter. Of course, there is dark matter and dark energy. I must make small remark here. How is it possible that almost empty space, with just 1 particle per 1 cubic meter, has significant energy levels (dark energy?) and that interstellar space, with density of 1 particle per 1 cubic centimeter, has gravity effect (dark matter)? There must be some form of the energy and matter that we can not see. Scientist call it dark energy and dark matter. It could be observable in the dark waves spectre not electromagnetic. It has certain properties that make it transparent but is it really open and crossable? Maybe more developed specie uses some sort of camouflage. Their matter appears as clear and through to cover their planets and structures. Anyway, intergalactic vacuum is closest thing to the nothing. There we have just 1 particle in the 1 cubic meter. Rest is crystal clear and unobstructed with quantum fluctuations and certain energy level.ž which is obviously still not nothing but we are closer to the idea. Now all you have to do is cool down that 1 cubic meter, using modified wavelenght lasers, to the near absolute zero, slowing the subatomic particles and emerging quantum pairs and practically decreasing the total energy to the nihil (0). Then you would have 1 static particle, dosen of frozen quantum pairs and no energy as long as precisely tuned lasers are cooling down our cubic meter. This is theoretically closest to the nothing.
Philosophic and linguistic nothing, as indeed found in the "ex nihilo" theology and different creation theories is not logically necessary, because if Time as a dimension was created with the Big Bang then anything existing prior is actually eternal and indestructible. Hence, any force or manifestation without time factor becomes immortal and needs no source cause. It just is. Quantum fluctuations just are. They happen and cancel each other without energy preservation violation. Total energy is always 0. Since, +1 and -1 equals zero (0) then zero (0) equals +1 and -1 in the same but reverse manner. It is the basic truth! Nothing is conditional! It has zero (0) total energy, due to the particle and antiparticle mutual cancellation, but still it is briefly manifested. People have wrong premises. They think of nothing exactly like nothing yet they can not see it anywhere only assume its emptiness. There is no nothing except as a human concept! There is only conditional nothing, with potential to express itself dually producing quantum fluctuations all over but always obeying the law of energy preservation which is zero (0) at all times!
Anti-matter exists in the anti-Verse or it is modified during the early Universe creation period to appear as a dark matter. Just think. Matter and anti-matter cancel each other. Why? Because they have the opposite charge. Proton has positive charge and anti-proton has negative charge. Like an electron. And anti-electron has positive charge. Like proton. But we reverse the structure of the elementary particles into its counterparts, that is into the opposite dimensions, beyond the mirror so to speak, hence the dark matter can not be physically touched nor seen with known electromagnetic spectre but it still is and has gravity effect due to its mass. Also more dimensions bring us closer to the string theory, or even further in the theoretical physics department, and can explain certain "phenomenons" I have encountered during my scientific work. Yes, I have seen things indeed that I wouldn`t discuss unless payed honestly, at least a million $. Not to spread a general panic among uneducated folks. Not to disturb traditional scientific circles. Not to reveal the truth just to see it negated by governments and mainstream (regime) media. I need more evidence. I need full spectrography of my discoveries and deeper scientific approach using expensive laboratories, experts and equipment. Oh my God! I already said enough. I stop here.