In how many years will the universe collapse into itself?

1. What these headlines are actually reporting: a single model, new dark‑energy fits

Several news outlets report on a 2025 JCAP paper by Hoang Nhan Luu, Yu‑Cheng Qiu and S.-H. Henry Tye that fits recent dark‑energy data and finds a best‑fit cosmological constant that is slightly negative, which would reverse expansion and lead to a Big Crunch — with numbers frequently quoted as a peak of expansion in ~10–11 billion years and a full collapse roughly 33–34 billion years after the Big Bang ^{[1] [2] [3]}.

2. The range of timelines you’ll see in reporting: why numbers differ

Different outlets summarize the model differently: some say expansion halts in ~10 billion years with collapse about 20 billion years after today (total ~33 billion years) while others quote ~11 billion until turnaround and collapse at ~33.3–34 billion years ^{[5] [1] [6] [2]}. These variations come from rounding, different descriptions of when contraction becomes rapid, and paraphrases of the authors’ best‑fit parameters ^{[1] [2]}.

3. How the model reaches a Big Crunch: the role of the cosmological constant and “axion”‑style fields

The paper’s mechanism is that dark energy may not be a fixed positive cosmological constant (Λ>0) but instead evolve; a small negative effective Λ or dynamical field can make gravity dominate later and reverse expansion. Reporters emphasize that the best‑fit from some dark‑energy surveys favors a small negative value in this model, producing a finite lifespan rather than eternal expansion ^{[1] [2]}.

4. Where mainstream cosmology stood before these results

Previously, most measurements were consistent with a flat geometry and a positive cosmological constant implying eternal expansion (the “Big Freeze” scenario); textbooks and long‑running reviews still treat continued expansion as the standard interpretation absent conclusive evidence otherwise ^{[7] [8]}. The new model challenges that but does not yet override the broad prior consensus ^{[7] [8]}.

5. How confident should you be? limitations and alternative viewpoints

Reporters and scientists quoted in coverage repeatedly note that current data “hint” at evolving dark energy but do not yet rule out Λ=0 or a positive Λ; the Big Crunch outcome depends sensitively on parameter choices and future data from surveys such as Rubin, DES, DESI and others ^{[1] [2]}. Some outlets frame the timeline as speculative or “one possible theory,” reflecting the provisional status of the claim ^{[3] [4]}.

6. Why popular summaries sometimes simplify to “we have X billion years left”

Journalistic pieces often convert model totals into time remaining by subtracting the current cosmic age (≈13.8 billion years), producing headlines like “about 20 billion years left” or “universe will end in 33 billion years” ^{[9] [10]}. Such simplifications hide model uncertainties and the fact that other well‑supported models predict no collapse at all ^{[7] [8]}.

7. Broader context: other far‑future estimates and competing research

Independent research threads give vastly different far‑future timelines — from effectively infinite expansion and heat death to exotic shorter windows for particular processes (e.g., black‑hole evaporation timescales or speculative radical revisions) — so this new Big Crunch estimate joins a wide landscape of theoretical possibilities rather than replacing them ^{[11] [8] [7]}.

8. Bottom line for readers

The claim “the universe will collapse in X years” currently rests on a provocative but not definitive reinterpretation of dark‑energy data yielding a best‑fit Big Crunch timescale near 33–34 billion years (expansion reversing in ~10–11 billion years) — a legitimate scientific result worth following, but not a settled fact; alternative analyses and the prior consensus that expansion may continue indefinitely remain viable until further observational confirmation ^{[1] [2] [3]}.