Tolman's paradox to Timescape

Einstein notices in 1907 that a faster-than-light signal would let an effect precede its cause; Tolman restates it in 1917; Benford, Book and Newcomb name it the antitelephone in 1970; Benford then spends ten years turning his own paper into a novel.

Kind: lineage · Span: 1907–1995 · Last reviewed: 2026-09-13

The line

The paradox is older than the particle. In §5 of his 1907 review for the Jahrbuch der Radioaktivität und Elektronik Einstein used the addition theorem for velocities to show that if a signal travelled at W > c "one can always choose v such that T < 0", so that "the achieved effect would precede the cause"; he found no logical contradiction in this but held that it "conflicts with the character of all our experience" enough to prove W > c impossible [HIGH] S2 (Einstein 1907, pp. 423–424, quoted in Weinstein 2012; the Einstein Papers site redirected to a portal announcement on 2026-09-13, and the register's CAU-1 carries the page reference as verified). Richard Tolman put the same argument into his 1917 textbook The Theory of the Relativity of Motion, §52, "Velocities greater than that of light", pp. 54–55: an impulse from A to B at speed u and a second frame moving at V; for uV/c² above one "the effect which occurs at B would precede in time its cause" [HIGH] S1 (read in the archive.org scan). Tolman does not cite the 1907 paper in that section (his one Jahrbuch reference is to a 1910 volume), so the link from Einstein to Tolman is one of content, which the historians of the subject treat as plain [MED] S2 (Kragh's 2025 history of pre-Feinberg tachyons calls Tolman's version "almost identical to Einstein's"). By 1923 the idea was public property: the Punch limerick about the young lady named Bright, who "returned on the previous night", is Tolman's paradox in five lines [MED] S2 (same source; the verse was by A. H. Reginald Buller).

The name came fifty-three years after Tolman. Benford, Book and Newcomb, all at the Lawrence Radiation Laboratory at Livermore, sent "The Tachyonic Antitelephone" to Physical Review D on 23 June 1969 and it appeared on 15 July 1970 (Phys. Rev. D 2, 263). Its abstract opens: the detection of faster-than-light particles "is reconsidered in relation to Tolman's paradox", and its second paragraph says that in 1917 Tolman showed that faster-than-light signals would allow "communication with the past", that is, "an 'antitelephone'" [HIGH] S1 (read in the archive.org scan; reference 7 is Tolman 1917, pp. 54–55, and reference 2 is Feinberg 1967). The paper's move is to show that the reinterpretation principle does not help: if Shakespeare types out Hamlet on a tachyon transmitter, "no amount of reinterpretation will make Bacon the author", because "the direction of information transfer is necessarily a relativistic invariant" [HIGH] S1. With two transmitters in relative motion a reply can reach the sender before the question, so tachyon experiments "must either yield negative results or give rise to causal contradictions". The register carries this as CAU-1, and it is why the catalogue's tachyon dossier is K0 and B-caus.

Then the co-author wrote the novel. Benford's own account, in his autobiographical essay for Contemporary Authors, is that "the underpinning of it all was a scientific paper on tachyons" written with Newcomb and Book in 1970. The novel "began as a short story", "3:02 P.M., Oxford" (If, September 1970); he then "tried another tack" with "Cambridge, 1:58 A.M." (Epoch, 1975), from which the English setting came [HIGH] S1 (essay read at encyclopedia.com). "Old Legends" (1995) adds the other half of the chain: Feinberg had been set thinking by Blish's "Beep"; Benford set part of the novel at Columbia "because of Feinberg"; Feinberg was pleased that his physics had spawned a novel [HIGH] S1 (essay as read for the Timescape dossier and quoted by Milburn 2019). Timescape (1980) is the paper made narrative: a modulated tachyon beam from 1998 to 1962, Tolman's paradox argued out in a Cambridge pub and the message rationed so that the loop does not close on a contradiction. The novel takes an escape hatch its author's paper had left open, both ends of the channel at rest on Earth, and it is the one work in this catalogue where the physics travelled with the word; the wider spread of the word without the physics is on feinberg-tachyon-outward.

Wells is the ancestor everyone assumes and nobody has documented. The Time Machine (1895) predates Einstein's argument by twelve years, but neither Einstein's §5, Tolman's §52 nor the 1970 paper mentions it, and the paradox is a consequence of the addition theorem, not of a novel. The link is a cultural one, that "returned on the previous night" was a joke readers of 1923 could get, and it is graded as such below.

The links

What is not sourced

• Einstein's page in the original. The §5 quotation is from Weinstein's translation with page numbers; the Einstein Papers site redirected to a portal announcement on 2026-09-13 and the Jahrbuch scan was not opened. The register has the entry marked verified from an earlier session, which is the basis for the confidence here.
• Tolman reading Einstein 1907. Almost certain and undocumented in §52. Tolman's preface or his 1934 Relativity, Thermodynamics and Cosmology p. 27, where he restates the argument, might carry the citation.
• "Time and Timescape" (1993). Located in JSTOR's table of contents for Science Fiction Studies 20(2); not opened, so its content is not used here beyond Milburn's pointer to it.
• The 1972 cosmic-ray claim as spur. Benford's Contemporary Authors essay says an Australian air-shower report of a particle above twice light speed set him asking "what if"; the catalogue's tachyon dossier records the Clay and Crouch paper as 1974 (Nature 248, 28). Benford's "1972" may be the observation date or a misremembering; the essay is the only source for the spur.
• Wells. The absence is the finding. A documented reading of The Time Machine by Einstein or Tolman or a statement by Benford that Wells was in his mind, would move the last row; nothing of the kind was found.

Sources

• Einstein, A., "Über das Relativitätsprinzip und die aus demselben gezogenen Folgerungen", Jahrbuch der Radioaktivität und Elektronik 4, 411–462 (1907), §5, pp. 423–424. S1. Not opened; quoted via Weinstein.
• Weinstein, G., "Einstein on the impossibility of superluminal velocities", arXiv:1203.4954 (2012), pp. 2–3 and notes 9–10. Read 2026-09-13. S2.
• Tolman, R. C., The Theory of the Relativity of Motion (University of California Press, 1917), §52, pp. 54–55. Read in the archive.org scan (theoryofrelativi00tolm) 2026-09-13. S1.
• Kragh, H., "Tachyons before tachyons: Lev Strum (1890–1936) and superluminal velocities", Eur. Phys. J. H (2025), arXiv:2504.18347, §4 for Tolman and the Punch limerick. Read 2026-09-13. S2.
• Benford, G. A., Book, D. L. and Newcomb, W. A., "The Tachyonic Antitelephone", Phys. Rev. D 2, 263 (1970), received 23 June 1969. Read in the archive.org scan (20210624_20210624_2321) 2026-09-13. S1.
• Feinberg, G., "Possibility of faster-than-light particles", Phys. Rev. 159, 1089 (1967). S1, as cited by the 1970 paper.
• Benford, G., autobiographical essay in Contemporary Authors, read at encyclopedia.com ("Benford, Gregory 1941-") 2026-09-13. S1.
• Benford, G., "Old Legends", in New Legends, ed. G. Bear and M. H. Greenberg (Tor, 1995), pp. 270–284. S1. Read for the Timescape dossier; p. 276 quoted in Milburn.
• Milburn, C., "Ahead of time: Gerald Feinberg and the governance of futurity", Osiris 34, 216–237 (2019), notes 5 to 8. Read 2026-09-13. S2.
• Benford, G., "Time and Timescape", Science Fiction Studies 20, 184–190 (1993). Not opened. S2.
• Benford, G., Timescape (Simon and Schuster, 1980). S1, via the Timescape dossier.
• Wells, H. G., The Time Machine (1895). S1, named only to record the absence of a link.