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WalterP

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Everything posted by WalterP

  1. Good call, Josh. Yes, the historical perspective of BBT is absolutely relevant to this thread. Many thanks for giving us an overview of the Catholic position on it. As I see it, the controversy centres on what both Craig and the Pope are calling, 'proof'. In this thread I've focused tightly on the Hawking - Penrose singularity theory of 1970, because that's the one paper that Craig relies on to give him that 'proof'. And, as we've seen, it's anything but the cast-iron proof he claims it is. Btw Josh, in a little while we'll examine two more items that throw a harsh spotlight on Craig's claims. The first will cover why the very earliest phases of the universe's evolution have never been directly observed, forcing scientists to theorize about it using inference and assumption. Just as Hawking and Penrose did in their singularity paper. But, if you can observe something, then you don't need to theorize about what it is - you can see it for yourself. But since we can't observe the very first instants of the universe, theorizing and inferring and assuming are all we have. How the hell a bona fide proof can be claimed, without observations and data is quite beyond me! This brings me on to the second item and I'm hoping that Disillusioned can help us out here. He's keen to hear what I've got to say about the philosophical underpinnings of science. Six months ago, on a whim, I ventured into a second-hand bookshop and bought this. A Short History of Truth: Consolations for the Post-Truth World. By Julian Baggini. 2017, by Quercus Editions Ltd. https://www.amazon.co.uk/Short-History-Truth-Consolations-Post-Truth/dp/1786488884 When I reached chapter five (Empirical Truths) I just knew that what was written there was vitally relevant to my five years of research into Craig's 'scientific' claims. Baggini focuses on the work of David Hume. https://en.wikipedia.org/wiki/David_Hume I won't go into the arguments here, but suffice to say, I was impressed by what Hume had to say about the dichotomy between the realm of the mathematically abstract and the realm of the physical world. As far as I can see, Craig grossly violates the division between these two realms. More on that to come. Lastly, picking up what you mentioned about the lengths that apologists will go to, let me acquaint you with a suspicion I have. If you listen carefully to Craig's dialogue with Penrose he fills in some personal details about his student days. His philosophical studies were leading him to conclude that his life was empty and meaningless and that the entire universe had no purpose to it. Into his time of growing despair came two things. First, his discovery of the singularity theories of Hawking and Penrose. Second, his encounter with a fellow student, who brought him to the foot of the cross, so that he gave his life to Jesus Christ. Coincidence? Or the hand of God, directing him to become a true believer AND arming him with scientific proof that the Bible was true? Josh, it's impossible to be sure, but if I were to put myself in Craig's place, I'd probably have concluded that God had selected me for the ministry and had given me a mighty apologetic weapon to use - scientific proof that the universe had a definite beginning. And, as they say, the rest is history. Since that time Craig's been persistently pursuing, pushing and promoting the divine truth that God set before him, without properly understanding it or seriously testing it. Ok, this is no more than a suspicion of mine and by rights I should confine myself strictly to the facts and not engage in this kind of speculation. But I think it needed to be said. Anyway, I'm currently working on some diagrams and graphics that should show why the very earliest moments of the universe's evolution cannot be directly observed by us. Once we have that on board we can then more readily understand why Hawking and Penrose had to use assumptions and not data in their singularity theorem. I'll be ready to go in a few days. Thanks again for that historical foundation. It'll become increasingly relevant and useful when we look into the background of Einstein's General Relativity and why he introduced the cosmological constant in the first place. All the best. Walter.
  2. Hello Disillusioned. What is interesting to me about this is that Craig argues that abstract entities can't function causally, and then immediately proceeds to give an entirely abstract description of God, which he claims solves his problem. This is very problematic for him, I think. Quite right. Very problematic. Since I've already established that Craig relies exclusively on just one paper by Hawking and Penrose to give him the 'definite beginning' he needs as a basis of his apologetic arguments, if we return to that document it can be seen that H & P are at pains to try and link their theory to physical reality. Without a link between the maths and physical reality, their 1970 paper remains a mathematical abstraction, entirely unconnected to our reality. Here's what H & P say. Page 538. 3. The Theorem We shall begin by giving a precise statement of our theorem. The form of statement we adopt is made primarily for the sake of generality and for certain mathematical advantages. But in order that the theorem may be directly applied to physical situations, we single out the main special cases of interest in a corollary. Page 544. Co r o l l a r y. A space-time M cannot satisfy causal geodesic completeness if, together with Einstein’s equations (3.5), the following four conditions hold: (3.20) M contains no closed timelike curves. (3.21) the energy condition (3.6) is satisfied at every point, (3.22) the generality condition (3.10) is satisfied for every causal geodesic, (3.23) M contains either (i) a trapped surface, or (ii) a point p for which the convergence of all the null geodesics through p changes sign somewhere to the past or (iii) a compact spacelike hypersurface. So, for the theory to be directly applicable to physical situations, all four points of the corollary must be satisfied. The theory remains a mathematical abstraction up until that point. Furthermore, the four points must be satisfied by data. Nothing else will suffice. We now know from the 1998 supernova data that (3.21) is not satisfied at every point. The energy condition (3.6) is the requirement for the observed cosmological constant to have a negative or zero value. It doesn't. Instead, its positive. Therefore all four points of the corollary are not satisfied and the theory cannot be successfully linked to the observed physical conditions of our universe. But there's a bigger and wider problem for Craig, Disillusioned. If we look back at the very beginning of the paper, part of the preamble says this. The theorem applies if the following four physical assumptions are made: (i) Einstein’s equations hold (with zero or negative cosmological constant), (ii) the energy density is nowhere less than minus each principal pressure nor less than minus the sum of the three principal pressures (the ‘energy condition5), (iii) there are no closed timelike curves, (iv) every timelike or null geodesic enters a region where the curvature is not specially aligned with the geodesic. So, what does this tell us? It tells us that in 1969 Hawking and Penrose were forced to use assumptions to make their theory work. There was no observed data for them to plug into Einstein's equations. There wasn't then and there still isn't now. This was going to be the third of my side-questions. "Why did Hawking and Penrose make these four assumptions in the first place?" The answer is that they had to use assumptions because nobody has any observed data from the very earliest moments of the universe's evolution. Everything we know directly comes from 380,000 years after the Big Bang. Everything we think we know about earlier than that is based upon inference and not direct observation. The Cosmic Microwave Background Radiation (CMBR) is responsible for the dichotomy between observation and inference. But I'll need another post to better explain just why that it is. If we accept that our data goes back to 380,000 after the Big Bang and no further, the fallout of this is devastating for Craig. How on earth can he claim that the definite beginning of the universe is 'scientifically proven' or 'scientifically confirmed' if the very theory in question relies on assumptions and not data? I'll leave it there Disillusioned and see what you have to say in response. Thank you. Walter.
  3. Hmmm... this is curious. Here's another relevant video that's dated Sept 4. Which would mean that it was made prior to the Oct 4 vid with Justin Brierley. WLC seems to misrepresent Penrose's Conformal Cyclic Cosmology in several places. If that were the case, then why didn't Penrose tackle Craig about these misrepresentations, when they met in Brierley's studio? I dunno. Anyway, I offer this up for your interest and can explain some of it, providing that it pertains (mostly) to this thread. Thank you. Walter.
  4. Thank you for this, TABA. Josh has already identified where Roger Penrose has changed his mind, since he Stephen Hawking wrote their singularity theory, back in 1969. I watched this video a little while ago to see if it was relevant to this thread and took notes accordingly. It is relevant and I was going to post it here after Josh, Disillusioned and I had dealt with a few side-questions. TABA beat me to the punch and that's not at all a problem. We can look at it now. I consider these three segments to be important. 10:30 to 12 :45 According to my notes, on the video, Penrose talks about what is 'prior to the Big Bang'. But, he's an old man now and not a very fluent communicator of the very complex matters under discussion. He doesn't come over very well when trying to explain what he means and Justin Brierley steps around the 12:45 mark, effectively closing him down. 19:50 to 22:30 Craig says, 'The mathematically abstract cannot be the source of the physical. The number seven has no effect on anything.' He's right. The H - P singularity theorem is a mathematical abstraction unless it can somehow be related to the physical universe by data or evidence. In this thread I will be showing how such data wasn't around in 1970, when the H -P theory was published and still isn't around in 2019. So Craig has scored an own goal here. There's NO data on the initial singularity itself. The theory was falsified in 1998 when supernova data was used to show that the universe possesses a positive cosmological constant. This falsifies the theory because the theory only works if the value of the constant (Lambda) is negative or zero. A note to Disillusioned. If you recall, at the beginning of this thread I mentioned David Hume. What he has to say is relevant to Craig's comments about the relationship between the mathematically abstract and the physical. More on that later. 31:06 Craig repeats his claim that the being responsible for creating the universe (God) would have to be uncaused, time-less, space-less, immaterial and enormously powerful, ethically good and omniscient. But he exclusively uses the H - P theory to do this. In that theory space and time have a definite beginning. So, the causal agent (God) must be outside of time and space. That is, time-less and space-less. Since the H - P was falsified twenty years ago, Craig has no scientific basis for his claim. Thank you. Walter.
  5. Matthew 6:24 24 “No one can serve two masters. Either you will hate the one and love the other, or you will be devoted to the one and despise the other. You cannot serve both God and money.
  6. Yes, Josh. And in the case of dark energy 'pushing' the universe open, that's something we can directly observe happening, unlike inflation, which we have to infer, from indirect lines of evidence. Which brings me to the subject of where would be best to go next in this thread? If you recall I offered the possibility of explaining these side questions, so that we can gain a deeper understanding of things. That is, before I continue with the overarching plan I outlined in my opening post. We've covered stages 1 through 4 and might be ready to move on to 5. But, lets just look at those side questions again. 1. What is the Cosmological Constant? (The 'push' that powered inflation and is now powering dark energy.) 2. How is it measured? 3. Why did Hawking and Penrose make these four assumptions in the first place? (Would help us understand where cosmological observations end and where theory takes over.) Please let me know if any of these are of interest to you. Thank you. Walter.
  7. Yes, Disillusioned. For those people who have been at all worried by WLC's persistence and certainty, this information should help allay their fears. I'll be waiting for JoshPantera to let me know how he stands re this thread, before moving on. That ok with you? Thanks. Walter.
  8. No, Disillusioned.. That's my error. We note, finally, that in Einstein’s theory (with ‘reasonable’ sources) it is only λ > 0 which can prevent gravitation from being always attractive, the λ term representing a ‘cosmic repulsion’. When λ > 0 it prevents gravity from always acting attractively. When its equal to or less than 0, gravity is not prevented from acting attractively. Gravity can only act repulsively when λ exceeds zero. So, by mistake, I'd reversed the meaning of what Hawking and Penrose wrote. Well spotted and thanks for that. Walter.
  9. Disillusioned, Please take as much time as you need and also feel free to ask me questions. This thread will proceed at whatever pace suits you and Josh. Many thanks. Walter.
  10. Dear Disillusioned and JoshPantera. In General Relativity (GR) the symbol used for the cosmological constant is Lambda. https://en.wikipedia.org/wiki/Cosmological_constant Now please follow this link to Hawking and Penrose's 1970 singularity paper. https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.1970.0021 We shall start here. Introduction (Pages 530 & 531) In this paper we establish a new theorem, which, with two reservations, effectively incorporates all of I, II, III, IV and V while avoiding each of the above objections. In its physical implications, our theorem falls short of completely superseding these previous results only in the following two main respects. In the first instance we shall require the non-existence of closed time like curves. Theorem II (and II alone) did not require such an assumption. Secondly, in common with II, III, IV and V, we shall require the slightly stronger energy condition given in (3.4), than that used in I. This means that our theorem cannot be directly applied when a positive cosmological constant λ is present. Here H & P summarize all of their previous work on singularities, from Penrose’s 1965 paper about black holes (I) and Hawking’s papers (III,IV and V) from 196 to 1967. Paper number 2 (II) is from 1966, by Robert P. Geroch and discusses Singularities in Closed Universes. H & P’s 1970 paper incorporates almost all of I through IV, with only two exceptions. Closed time like curves need not concern us now, but I can explain about them, if asked. The important exception to all of singularity theory is the second one. Singularity theory cannot be directly applied to our universe when a positive cosmological constant λ (Lambda) is present. As we have seen, in 1998 just such a positive value was observed, falsifying singularity theory. H & P go on to say, However, in a collapse, or ‘big bang’, situation we expect large curvatures to occur, and the larger the curvatures present the smaller is the significance of the value of λ. Thus, it is hard to imagine that the value of λ should qualitatively affect the singularity discussion, except in regions where curvatures are still small enough to be comparable with λ. The above paragraph needs a bit of explanation. H & P expected large curvatures of space-time to occur at and near the Big Bang itself. They expected that these large curvatures would overwhelm the significance of λ, making it an unimportant factor in the very earliest moments of the universe. They found it hard to imagine that λ would have a huge value. So, they couldn’t see how the expected small value of λ would affect their singularity theory. But the salient point here is the historical context in which H & P were formulating their singularity theory. They performed their work from 1965 to 1969, publishing in 1970 and only working in the classical regime of GR. At this time the very idea that Inflation could play a role in the very early universe was largely unknown. Theorists like Alan Guth, Alexei Starobinsky and Andrei Linde didn’t bring their inflationary theories to fruition until late 1979 and the early 80’s and inflation goes further than GR, involving the use of Semi-Classical Gravity. https://en.wikipedia.org/wiki/Semiclassical_gravity This is a kind of hybrid mix of GR with particle physics. Since H & P were working exclusively with GR in their singularity theory, they couldn’t have anticipated that inflation would yield a brief period where the value of λ would be tremendously large. Large enough to totally overwhelm the large space-time curvatures they factored into their theory. In the brief moment known as the Inflationary epoch, gravity is reversed – changing from attractive to repulsive. Under the normal conditions of GR, gravity only attracts massive objects and only curves space-time in a way that causes these objects to fall together under their mutual gravitational attraction. But with inflation, that scenario is violently reversed. Instead of the universe contracting, the universe is caused to expand with incredible speed, carrying all of its contents with it. In terms of the cosmological constant, λ has a huge positive value, one that H & P did not anticipate. And this explains why their singularity theory cannot work when λ has a positive value. In inflation, λ causes gravity to ‘push’, while in GR λ can only ‘pull’ or keep a kind of status quo, balanced exactly on the knife-edge between pull and push. The three types of Friedmann universe, known as Closed, Flat and Open universes are illustrations of these three scenarios. In Closed universes, λ is negative and only pulls everything together in a Big Crunch. In Flat universes, λ is balanced exactly at zero and the universe ‘coasts’ forever, ultimately ending in a Big Freeze. But when λ is positive, we get an Open universe, where space-time is being ‘pushed’ apart by some kind on energy that is present in space-time itself. These days we call this Dark Energy. H & P confirm this in their 1970 paper, when they write this. The energy condition (3.4) used here (and in II, III, IV and V) has a very direct physical interpretation. It states, in effect, that ‘gravitation is always attractive’ (in the sense that neighbouring geodesics near any one point accelerate, on the average, towards each other). Our theorem will apply, in fact, in theories other than classical general relativity provided gravitation remains attractive. Which means that singularity theory can applies, but only when Lambda is negative or zero, not when it is positive. H & P go on to say this. We note, finally, that in Einstein’s theory (with ‘reasonable’ sources) it is only λ > 0 which can prevent gravitation from being always attractive, the λ term representing a ‘cosmic repulsion’. i.e., gravity only acts normally and attractively, when λ > 0. That is, when Lambda is positive, exceeding zero. And H & P show this in their equations. P 539 / 540. To incorporate a cosmological constant λ, we would have to replace Tab in the above by Tab + λ K-1gab. Thus, (3.6), as it stands, would still imply (3.4) so long as λ [is equal to or less than] 0. Again, H & P stipulate that their theory only implies an initial singularity if λ is equal to or less than zero. That is, if λ is more than zero and has any positive value, then their theory does not imply the existence of an initial singularity. When we reach the Corollary, H & P write this. (P 544) (3.21) the energy condition (3.6) is satisfied at every point, What this means is that as far as they were concerned, the energy condition of their theory was satisfied at every point in the region of space-time under examination. Or rather, it would be, provided that λ was equal to zero or had a negative value. However, since inflation yields a massively positive value, the energy condition is not satisfied at every point. Even if we ignore the inflationary epoch, in 1998 it was shown that the expansion of the universe was accelerating, indicating that as far back as 5 billion years ago, the universe possessed a small positive value of λ. Since ANY positive value, no matter how small signals the death knell for singularity, H & P’s theory was falsified just as effectively by Dark Energy as Hoyle’s Steady State theory was falsified by the detection of the CMBR. Finally, H & P write this. We may interpret failure of the causal geodesic completeness condition in our corollary as virtually a statement that any space-time satisfying (3.20)-(3.23) ‘possesses a singularity’ This causal geodesic incompleteness is the ‘definite beginning’ which Craig claims that the H & P singularity theory proves. But, as we have seen in this thread, that proof rests upon a very important condition. That the cosmological constant Lambda λ in the universe must have either a negative or zero value. Inflationary theory posits a massively-positive λ in the very early universe and Craig denies that inflation ever took place. Its true that inflation cannot be observed and has to inferred from other lines of evidence. But Craig accepts that Dark Energy is accelerating the expansion of the universe today and we can observe this happening, today. It need not be inferred, we can see it happening. So Craig's position is untenable. To deny one manifestation of λ but accept another is to be inconsistent. Therefore Craig’s cosmology is shown to have failed before he even began promoting it on Reasonablefaith. Thank you. Walter.
  11. Justus, I think Disillusioned has come up with an excellent solution and I, for one, would be very happy if you were to take him up on it. Thank you. Walter.
  12. A gentle reminder to LogicalFallacy and Justus of the context of this thread. What is up for discussion in this thread is the relationship of William Lane Craig's cosmology to the currently accepted mainstream cosmology, which is the Lambda Cold Dark matter model. Lambda is the symbol used to denote the cosmological constant, which is what JoshPantera, Disillusioned and I are discussing. Therefore, while the 'common Christian interpretation' of creation from nothing does overlap Craig's cosmology, the Catholic interpretation does not and is therefore off-topic. So, if LogicalFallacy were to respond to Justus about that Catholic doctrine, both of you would be taking this thread off-topic. Please discuss this in another thread and respect the topic of this one. Thank you. Walter.
  13. Hello again Disillusioned and Joshpantera. Just to recap... we're about to dip very lightly into the Hawking - Penrose singularity theory to see exactly where they exclude the possibility of their theory applying in a universe with a positive cosmological constant. I promise (hand on heart) that this will be the only time in this thread that we touch upon the actual equations. After that the rest of our journey will be in more-or-less plain English, with various technical terms and concepts explained with diagrams and graphs. Oh... and let's not forget that I also offered the possibility of us entertaining some relevant side-questions. 1. What is the Cosmological Constant? 2. How is it measured? 3. Why did Hawking and Penrose make these four assumptions in the first place? Thank you. Walter.
  14. I agree, Josh. Craig has failed on many levels. If I were to list the ones we've covered so far in this thread, it would read like this. 1. He relies exclusively on just one single theory, one that was falsified by evidence in 1998, almost a decade before Reasonablefaith started up. 2. He claims that General Relativity is the only fundamental theory science needs to give a complete and correct description of the universe, denying quantum theory. 3. Yet we know that there are four fundamental forces, three of which (electromagnetism, the weak and the strong nuclear forces) require quantum theory. 4. Elsewhere in Reasonablefaith Craig mentions the finely-tuned values of all four forces, contradicting his claim that only General Relativity (which describes only gravity) is fundamental. But I have to ask this question. "Why should we be surprised at Craig's unwillingness to let go of his failed cosmology?" Look at the example of Fred Hoyle. https://en.wikipedia.org/wiki/Fred_Hoyle Even in the face of overwhelming evidence against the Steady State Theory, he continued to reject the possibility that the universe had a beginning. His primary motivation for doing so was his personal distaste of Theism. So he was a kind of anti-Craig. Hoyle and Craig can be seen as diametric opposites of each other. For Craig, an eternal universe without a beginning is unthinkable and emotionally unacceptable. For Hoyle, a transient universe with a beginning was equally unthinkable and equally emotionally unacceptable. In both cases, both men refused to let go of their failed cosmologies, even though it would be rational and reasonable for them to do so. So Josh, I suspect that what we are looking at in both men is a deep-seated and unyielding irrationality. Just as Hoyle went to his death believing the universe to be eternal, I suspect that Craig will do the same, believing to his dying breath that only the Hawking -Penrose Singularity theorem is correct and that the universe had a definite beginning. Thank you. Walter.
  15. Interesting video, Josh. Thanks for posting it. Btw, how are you getting on with the links I posted on Friday? You'll have seen that we seem to live in a universe with a positive cosmological constant. Which falsifies the very theory that Craig bases his whole cosmology on. This one. https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.1970.0021 Thank you. Walter.
  16. Hello again, Disillusioned. Looking back I realize that I goofed in my Saturday post. I should have included links to where Craig actually said the things I accused him of. Let me set the matter straight right now. https://www.reasonablefaith.org/writings/popular-writings/science-theology/the-scientific-kalam-cosmological-argument/ Please follow the above link and scroll down to where it says, Exceptions to Singularity Theorems. This is what Craig writes next. Five possible exceptions to the Hawking-Penrose singularity theorems conveniently distinguish four classes of non-standard models which provide possible alternatives to the standard Big Bang model. The H-P theorem also has the obvious, but implicit, condition that GR is fundamental; that is, it is a complete as well as correct description of conditions within our universe. It seems that I didn't get the quote quite right. I said, 'complete and concise' but Craig actually says, 'complete as well as correct' when talking about GR. But he's still wrong. Even though GR is fundamental, its not fundamental on its own. It simply cannot give and complete and correct description of conditions within our universe. For that you would need the other three fundamental forces - electromagnetism and the weak and the strong nuclear forces. Craig is trying to exclude all mention of quantum mechanics from his cosmology. Why? Because the Hawking - Penrose Singularity theorem uses ONLY GR and doesn't use quantum mechanics in any way, shape or form. But, as I mentioned on Saturday, he then contradicts himself by using quantum mechanics to give him examples of fine-tuning in the universe. He can't exclude QM in one place and then agree with it in another. Like this. https://www.reasonablefaith.org/podcasts/defenders-podcast-series-2/s2-excursus-on-natural-theology/existence-of-god-part-14 Question: It is a little hard to ponder how fine tuning of the constants and the arbitrary quantities can be embedded into a singularity. For example, it is a little hard to imagine how a singularity could have any entropy at all. Have astrophysicists gotten far in how this works? Answer: No. In fact, what we are talking about here, when I talk about the early universe, I do not mean the singularity. Some of these constants and quantities result from quantum phase transitions that the universe goes through very, very early. You have first this unified theory – some sort of a quantum theory of gravity – in which there are not separate gravitational particles or electromagnetic forces and so on. You just have a unified force. Then you have this so-called “GUT Era”5 where you have a grand unified theory where gravity breaks loose from the other three fundamental forces of nature, and that will then involve this fine tuned gravitational constant. Then you have it break down further into the fundamental forces of nature like gravitation, electromagnetism, the weak force, and the strong force. As the universe goes through these quantum phase transitions, what happens is these finely tuned values just fall out one after another – inexplicably because these are supposed to be indeterminate phase transitions. When I said “from the beginning,” I didn’t mean from the singularity. I meant from the very, very early universe; but in fact they do fall out serially as the universe goes through these phase transitions. He 100% contradicts himself, Disillusioned. Thank you. Walter.
  17. Pantheory. Please note the content and context of Disllusioned's latest post. He is talking about Craig's cosmology and it's relationship to mainstream cosmology - nothing else. Now please stop taking this thread off topic. Thank you. Walter.
  18. Pantheory. The context of Disillusioned's comments were about the relationship of William Lane Craig's cosmology to mainstream cosmology. "Alright, so I've read or skimmed the papers linked to above. They do indeed provide support for a positive cosmological constant. My understanding prior to this discussion was that this is not really in serious dispute amongst most cosmologists these days, but I could be wrong about that. I haven't exactly been keeping up with these things recently. In any event, it is certainly problematic for the Hawking/Penrose theorem if the cosmological constant is indeed positive, which it seems to be. I think Hawking recognized this, which is probably why he eventually rejected his own theorem. But this leaves the Craig argument without much of a leg to stand on. But, of course, he would not admit this." The context of his comments is given in the highlighted section and are entirely within the proper intent and content of this thread. You are taking them out of context by comparing them to an alternative or competing cosmologies. Cosmologies that play no part in this thread. Doing that is taking this thread off-topic. Please stop doing so. Thank you. Walter.
  19. Thanks for this, Pantheory. Would you please take a look at the disclaimer I posted at the beginning of this thread? If you read it you'll see that what's under discussion here is the cosmology of the Christian apologist William Lane Craig. What he accepts as being scientifically valid and what he doesn't. You'll also see that I've clearly outline my personal position as being a neutral and non-committed one. I do not actually claim to support, agree with or endorse any of the science matters discussed in this thread. When I point out something that he misunderstands I am not saying or implying that the science in question is actually right and correct. I am saying that he is wrong in his understanding of it. In doing that I am not holding up mainstream cosmology as being, 'the right answer'. Instead I am pointing out that Craig's personal take on cosmology is incompatible with mainstream cosmology. I leave it up to the other members of this forum to make up their own minds as to which position they want to take. So, can you see where what your last message is doing to the intent and content of this thread? It's taking it off-topic. Your personal cosmology is not under discussion here. Nor is mine. Nor is Disillusioned, Joshpantera's or any other members. Only Craig's. Naturally, such items as the Big Bang, Inflation and Singularity theory have to be discussed here - but that's only because Craig dwells upon them in his website. The fact that they discussed here is not an endorsement of any of them. This situation is an exact parallel to the many theological threads in the Lion's Den. Their themes and topics need not be held to or supported by the members debating them. Do you see that? I hope so. To debate something is not to necessarily accept it or promote it. Can I therefore politely request that you respect the intent and content of this thread and not make it a place where competing cosmologies are discussed? That this thread remain a place where only Craig's cosmology is compared to mainstream cosmology. Thank you. Walter.
  20. I agree, Disillusioned. In my opinion Craig is entirely sincere in his beliefs. But when it comes down to admitting that his much-valued singularity theory is actually falsified by evidence, could he bring himself to do it? Without it he has no scientific basis for at least two apologetic arguments and possibly more. He loses the KCA, which relies on there being a definite beginning of time and space to introduce the notion of a cause of the beginning of these things. He also loses a way of identifying certain aspects or qualities this cause must have. Since all of time and space came into existence at the initial singularity, the cause of the singularity cannot be located anywhere within time and space. That would violate causality. Therefore, the causal agency of time and space must have be, in his words, 'timeless and spaceless'. From there he goes on to argue that an eternal spirit (i.e., God) is the best candidate for this causal agent. Such an agent requires neither time nor space to exist in and no material body either. But, without Hawking and Penrose's singularity theorem, Craig loses the basis for this argument too. Perhaps the loss of so much is just a bridge too far for him? As to Craig's ignorance of matters cosmological,here are a few quick examples. He denies that Inflation took place in the earliest moments of the universe, but accepts that dark energy is causing the universe's expansion to accelerate. Yet both of these seemingly unrelated things are caused by a positive cosmological constant. Apparently he doesn't understand that both invalidate the Hawking - Penrose singularity theorem. Denying one isn't enough. He has to deny both to be consistent. He claims that General Relativity on its own presents a 'complete and concise' description of the universe at a fundamental level. His words. Which is a denial that science recognizes four fundamental forces and requires all four to give a proper description of the universe. The four being, gravity, electromagnetism, the strong and the weak nuclear forces. Yet, when Craig makes his fine-tuned universe arguments, he uses particle physics to give him examples of the precision to which nature is finely-tuning. Sorry, but that won't work! If you deny everything except general relativity (a theory of gravitation) then you can only use GR in your examples of fine-tuning in nature. But GR won't give you anything to do with protons or hydrogen atoms or the Higgs boson. GR cannot help you because it only functions on scales larger than the molecular, the atomic and the sub-atomic. Another contradiction. Thank you. Walter.
  21. Hello Pantheory. With all due respect, I think you've misjudged the faith-driven mindset of Christians like Craig. Changing their minds by shifting to a different paradigm or a competing theory is simply something they will never, ever do. If you watch this video... ...you'll see Craig being refuted, corrected and schooled by the theoretical physicist Sean Carroll. But does he accept the refutations and corrections? No. When Carroll takes the stands for the second time he points out that Craig has simply repeated his earlier points, requiring Carroll to go back over the same ground again. Craig's total refusal to accept that he is wrong and mistaken on many points is, I'm sorry to say, all too symptomatic of the unwavering strength of Craig's faith. He just KNOWS in his heart that the universe had a definite beginning and no amount of debate or evidence is ever going to shift him on this. By the witness of the Holy Spirit in his heart he KNOWS that science agrees with and confirms scripture. How do I know this? Watch, listen and learn. Thank you. Walter.
  22. Thanks, Disillusioned. Of those eight links, the Edge article by Raphael Bousso is, by far, the most accessible and easily digestible. If I were to suggest a reading plan for you (and Josh), please don't delve too deeply into the equations, the calculations and the esoteric nomenclature. If possible, it would help if we could look at a few of the symbols in the Hawking - Penrose paper. But only to further our understanding of why their singularity theory doesn't apply in a universe with a positive cosmological constant. That is, in our universe. Thank you. Walter.
  23. Disillusioned and Josh, Here are a few side questions that are relevant to our discussion. I recommend that if you want a better and fuller understanding of this entire issue, you would do well to look at them. As per usual, I'm happy to help explain and clarify, where I can. 1. What is the Cosmological Constant? 2. How is it measured? 3. Why did Hawking and Penrose make these four assumptions in the first place? And here's a handy tip for finding your way through the science papers I linked to. Once you follow the link and arrive at the page in question, press Control F. A Search box should open up for you. Type in the word, 'positive' and start the search. A scrolling bar should appear on the right of your screen, with orange lines indicating where the word positive occurs on that page. This will save you laboriously reading through acres of dense text and complex equations. You should also be given a count of how many times the word positive occurs on the page. By looking only at where it's mentioned you should be able to get a broad overview of what cosmologists think about the value of our universe's cosmological constant. Thanks again. Walter.
  24. Dear Disillusioned and Joshpantera, If it’s ok with you (please lmk otherwise) I’m going to move on to Step 3, where we’ll look at exactly where in Hawking and Penrose’s theory WLC comes unstuck. If you follow the link and just skim quickly over the whole thing, you’ll see that it breaks down in this order. https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.1970.0021 Title, Authors and Dates. Abstract (A brief overview) 1. Introduction. 2. Definitions and Lemmas. 3. The Theorem. Corollary. Proof of the Theorem. References. Appendix. Today we need to focus only on a part of the Abstract, specifically, the four physical assumptions that Hawking and Penrose made, which the theorem must satisfy if it applies to our universe. Should it fail to satisfy all of them then the theory will not apply to our universe. The first assumption is the one requiring our attention. The theorem applies if the following four physical assumptions are made: (i) Einstein’s equations hold (with zero or negative cosmological constant), So, the $64,000 question that’s now screaming to be answered is this. “Do we live in a universe with a cosmological constant of a negative value, of a zero value or of something else?” The answer to this question will tell us if Hawking and Penrose’s theory applies to our universe or not. I will let the following links supply the answer to the big question. https://arxiv.org/abs/1706.07482 http://physics.princeton.edu/~steinh/lambda16.pdf https://ned.ipac.caltech.edu/level5/Carroll2/Carroll2_2.html https://www.edge.org/response-detail/27194 https://en.wikipedia.org/wiki/Cosmological_constant https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5256042/ https://arxiv.org/ftp/arxiv/papers/1711/1711.06890.pdf https://cds.cern.ch/record/485959/files/0102033.pdf Thank you. Walter.
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