new scientist latest issue covers this paper SU(5) Unification without Proton Decay Bartosz Fornal, Benjamin Grinstein (Submitted on 26 Jun 2017 (v1), last revised 13 Nov 2017 (this version, v2)) We construct a four-dimensional SU(5) grand unified theory in which the proton is stable. The Standard Model leptons reside in the 5 and 10 irreps of SU(5), whereas the quarks live in the 40 and 50 irreps. The SU(5) gauge symmetry is broken by the vacuum expectation values of the scalar 24 and 75 irreps. All non-Standard Model fields are heavy. Stability of the proton requires three relations between the parameters of the model to hold. However, abandoning the requirement of absolute proton stability, the model fulfills current experimental constraints without fine-tuning. Comments: 5 pages; v2: accepted by Physical Review Letters Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th) Cite as: arXiv:1706.08535 [hep-ph] (or arXiv:1706.08535v2 [hep-ph] for this version) with some reviews and quotes by particle HEP physicists that its promising. a modification of SU(5) GUT, without SUSY, that makes protons stable.