This isn't necessarily an agreement or disagreement, but I think it should be clarified that, in physics, the speed of light in a vacuum is constant. However, light travels more slowly when passing through material, so its speed can vary depending on the medium.
Based on what Eldemade posted, I believe the statement that the speed of light is not constant refers to this phenomenon, since that distinction is stated directly.
Not exactly. That statement is about the atmosphere slowing down Suimu itself (got damn the Paddler mistranslation is hilarious), it's not about slowing down light itself.
This was a divine feat, but Ultima’s real target was Paddler, their boss. It swam
through the sky, changing form constantly and seemingly able to set its speed to whatever it wanted at any time, no acceleration required. That meant it could go at top speed from the start, and its maximum combat speed was near the speed of light. Light moves approximately at 880,000 times the speed of sound, and Paddler wasn’t quite there, but it was beyond close enough. The atmosphere was slowing it down a lot, but it was still moving at over 100,000 times the speed of sound, making it impossible for ordinary humans to even see the cryptid. OTL V22
And suim by itself is near the speed of light (relativistic) even in the Otherworld, not SoL.
I mean, Rimuru already knew of and had access to SoL attacks since Volume 5. The "no one can travel at SoL unless in a vacuum" isn't really something super abstract that Ciel has to tell Rimuru in the literal last Volume.
I'll try to give another example. Let's say we go by Elde's assumption that IP is at best SoL; then: SoL doesn't work in the suspended world to begin with:
Neither light nor sound could travel at all. If you wanted to perceive things around you, the only way was through the unique particles around you, ones at the very core of creation—even smaller than photons or spiritual particles. These were the “data particles” Ultima mentioned, and Luminus could understand that well enough. OTL V21C1
On top of that, information particles are quite literally smaller than photons (which by definition are massless), so, uh, you have a speed of light not working and a speed of light clearly working in the suspended world. I think that should get you the idea of what "SoL isn't constant" works. IP moves at speed such that constant speed = Suspended World speed + SoL, not SoL alone. So really, Rimuru is more so surprised that they are travelling at a speed beyond their constant speed. And that is quite literally the highlight of that scan:
We won't be able to meet anymore, goodbye. While I was bewildered about how I should deal with it, a horizontal slash passed through the location where I was. Detecting the danger and evading it, I confirmed its identity. It was several tentacles. That was dangerous. It's not that I had let my guard down, but its speed was on a completely different level from before. Faster than light seriously, it was faster than light.
Could it be that in the Stopped World, because the laws of physics do not apply, faster than light movement is possible?
No, in the first place, since the speed of information particles is constant, I never thought such a phenomenon could be possible. While praising myself for having been able to react and engaging in a bit of self congratulation I continued dealing with Ruvelje's fierce assault. Directly ahead, the giant body remained there as it was. Only the tentacles that had separated from its tail were launching attacks as if tracking me. If it were only that, I could somehow manage, but feeling a chill, I turned my eyes toward Ruvelje's gigantic body. An intense sense of incongruity.
Translated by Raiki
I'll also try to summarize the replies I gave to the other guys above, including ones that prove Elde's argument (to my understanding) is wrong:
- Speed of Light isn't constant doesn't just refer to "vacuum and non-vacuum" stuff.
- IP movement is constant and instantaneous, it happens in 0 time lag and IP can transmit into to any point in time.
- The Convo between Rimuru and Chloe wasn't instantaneous because Rimuru wasn't a dlf yet.
- Being able to interfere with IP =/= being a dlf, even when it comes to speed.
- Unless you're a dlf, even if u can interfere wog infons, you need time to process the info you receive from IP since they aren't...part of your own body. That is what creates the lag, essentially.
- The "IP travels to different coordinates with 0 time lag " is a statement that comes after this whole discussion of why interfere with infons isn't enough and being a dlf is required.
You cannot keep asserting that I'm derailing when none of that is happening. Also no, I don't need to downgrade the result of the previous thread in order to contest the current proposal not to mention, "this thread works on the assumption that infinite speed is accepted", you do realize you just proved what I said right? The purpose of splitting it into two threads is piggyback off the previous one otherwise what do you mean that it works on the assumption it has been accepted if not "if the previous one was okay then this one must be too"? You're literally hiding one thread behind another and trying to eliminate any opposition in that manner.
Then go get the previous thread rejected. You're overwriting something that was quite literally accepted like a month ago in the part 1 of this thread "because I wasn't there", yada yada
Go make your own thread to downgrade that infinite speed if u wanna argue it isn't speed to begin with. It's not me piggybacking on that thread, this is quite literally how vsbw works. We aren't supposed to just dump text walls upon text walls into a single thread and expect staff to evaluate it with a peace of mind.
Honestly lame how you're trynna circumvent something already accepted with something akin to "fight me if you have the guts"
The speed of information particles is constant, the same goes for information transfer between them however, the two aren't mutually inclusive. Data transfer through radio waves doesn't mean the physical movement of anything that emits radio waves is at the speed of light. It's as simple as that
Uh.... Yo info know our infinite speed is quite literally "relativistic/hypersonic/whatever normally, Infinite in digital nature"??
So this doesn't even matter cuz what you're saying applies only outside the suspended world or when a person isn't in digital nature at some moment, meanwhile our infinite speed is ONLY when they are in digital nature, when they are composed of data particles that trasmit information.
It never was a contention however, precisely because they are unhindered by and unfettered from space and time to an extent, information doesn't need to pass through space or any media for that matter in order to be transmitted neither is there any time taken in the transmission of said information
My logic has zero implications of this as their BDE is more about them being unbound from space and time so it doesn't factor into the rate of information transfer. BDE 1 characters are simply put immune to conventional spatial and time manipulation and quite frankly, I'm starting to have doubts if BDE 1 should even remain given that matter is composed of information particles and they have mass meanwhile, BDE 1 is supposed to lack spatio-temporal features.
Anyway, none of this rules out what I said, they are simply not fettered by constraints such as space and time so both distance and time aren't applicable to their information transfer (given they cannot physically travel through time on their own).
"Never a contention" meanwhile proceeds to argue further about BDE and also forgot what you said in the last page; "Thanks to it's BDE 1 nature, this isn't a case of time being undefined but rather distance and time not being applicable so there's no speed at all". Negative tracking skills store
The main character of the series with the supergenius supercomputer ability himself confirms it isn't a matter of speed. It just merely appears that way. So far, there has been nothing brought forward scans, context or otherwise to refute this.
They said "it isn't a matter of
surpassing the speed of light", not that "it isn't a matter of speed". Holy twisting words
This is my last comment here, because I’m honestly tired. I already know that after all this effort, in the end, that group of staff will just agree as usual.
As I told you, Rimuru himself admitted that the speed of light is the maximum speed he has dealt with up to this point. This is something Rimuru himself stated, and the text implies that the speed of light is the highest speed any character in Tensura can reach outside all spatial and temporal constraints.
Even though Rimuru himself acknowledged this, you are trying to ignore it and create interpretations to justify a text that is already clear and has no ambiguity. If Rimuru heard you here saying that his speed is “immeasurable,” he himself would be surprised and would not believe where you got that from, because he is personally completely surprised even by the speed of light. So what if you told him about infinite speed or immeasurable speed? I think Rimuru himself would be shocked to death.
Not even getting my argument

The speed of light isn't constant while speed of IP is yada yada, that's why he's surprises cuz ivarage's information particles are illogically moving beyond their law of constant speed.
You're welcome to stop replying tho ¯\
(ツ)/¯
More evidence to the pile from elde
There's time taken in sending out an infon (I'll be calling it that from now on) to observe the surrounding and recalling it to obtain that data which proves what I have been saying. Information transfer= instantaneous, movement of infon= not instantaneous therefore, rate of information transfer =/= physical movement speed of infons.
Unsurprisingly what the first thread jinxed came out to be true. Larpers are using this argument while ignoring the whole context.
This is before Rimuru became a dlf. Ciel can talk to him instantaneously because she's a part of him, they share the same soul and all. But Rimuru himself isn't a dlf; he flies out info particles and receives back info, but there would still be a time lag (cuz duh, he isn't a dlf yet). Simply being able to interfere with IP is NOT the same as being a dlf yourself:
Well, Chloe had come, but I still remained motionless. In other words, it was impossible to reply to her—
«No problem. It turns out that information particles are unaffected by time or space and can transmit information to any point in time. This means that they can transmit thoughts even in a suspended world.»
Is that so? The conversation between me and Ciel-san was happening instantly. However, the voice I heard from Chloe had a slight time difference. The reason for this remained unknown though, right? If the information particle was unaffected by time and space, then wouldn’t it make sense that communication would be instantaneous as well?
«I am a part of Master, so I am not affected by time at all. However, if you want to know what’s going on outside in the suspended world, an information particle needs to be flown out to grasp the information of the surroundings—»
Hmm, that’s hard to explain. In short, the information particle is not affected by space-time, so it can move in any situation. That’s why, by interfering with the information particle as a substitute for magicules, you can maintain your vision and transmit your thoughts. In other words, interfering with the information particle was not enough to move in this situation. Chloe seemed to be talking normally, but I guess we shouldn’t confuse her with the real world.
I thought that she was using ‘Thought Acceleration,’ but it seems that this was not the case. Apparently, we were just exchanging information particles with no time lag, and it was possible because we shared the same ‘soul.’ In that case, if I wanted to communicate my intent to a third party in this ‘Suspended World’—
«You can imprint your will on the information particle and hit the other person.»
This may sound rough, but I understood it well. Ciel-san could now interfere with the information particle, so it’s possible to reply. In the first place, the reason why I could see what was going on around me now was because I was reflecting the information particles. I wondered whether or not the speed of the information particles was constant in this ‘Suspended World,’ but I was glad to hear that the conversation was established. Slimereader
You can make your thoughts travel to the other party at infinite speed, but that doesn't mean the time you take to process the reply is also infinite, UNLESS You're a dlf.
So larp better next time
Talk about a double edged sword. On the one hand, you may be paving a way to immeasurable speed by eliminating anti-feats but on the other hand, you bring into question the validity of all SoL statements in the verse and end up downgrading them so I'll just leave you withthe advice of not going down this route, though the choice is ultimately yours.
P.S: The speed of light is actually not constant. In a vacuum it's 300,000,000 m/s, in air it's 299,792,458 m/s, in water it's about 225,000,000 m/s. Also, he literally said "conceptual topics".
Oh for sure for sure. Our SoL from early volumes is based on a numerical value (10,000km divided by 0.034s), not just a direct statement. Goodluck downgrading that.
Anyways, right now I'm just really exhausted from some drama (outside vsbw) and don't have the mental or physical stamina to keep replying. I'll be taking a break for a few days till things hopefully resolve (really hope so, because this is depressing for me too ;-

, so don't expect a serious or lengthy reply from me.
Will the powerscaling blood that runs through my veins overpower this depression? I don't know, maybe, maybe not. But I thought I ought to give a notice in case I do indeed disappear for some time.
Ah, and,
@AlexSamDen goodluck with the CRT, homie