Electroweak Baryogenesis and Standard Model CP Violation

Eric Sather; Patrick Huet

REVIEW

Electroweak Baryogenesis and Standard Model CP Violation

Patrick Huet, Eric Sather

High Energy Physics - Phenomenology · Submitted 20 Apr 1994 · 24 references

Pith's verdict: A solid, honest negative result on CKM-driven electroweak baryogenesis; the calculation holds, but the abstract's blanket exclusion outruns what was computed.

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arXiv IDhep-ph/9404302 (version 1)

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CitationEric Sather, Patrick Huet. "Electroweak Baryogenesis and Standard Model CP Violation." arXiv:hep-ph/9404302 (1994). https://pith.science/paper/Z4UBLKNO

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Editor's note

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The thing to know: the headline conclusion here is not theirs. That QCD damping kills the Farrar-Shaposhnikov mechanism is GHOP's result, and Huet and Sather say so in the abstract and again in Section 5.2. What is theirs is the physics picture and the machinery: reading the damping rate as a finite coherence length, ℓ = 1/(6γ), and building a Green's-function expansion in which every path through the bubble carries exp(−L/2ℓ). That is a genuinely useful way to see why only a thin outer skin of the wall contributes, and it turns a numerical accident into a power count in Mℓ and δp·ℓ. The new CP-odd invariant D^d in eq. (61) is a real addition, distinct from the Jarlskog determinant. They are also careful where it counts: the up-quark numbers are labeled upper bounds because the top is far off shell, and the thick-wall discussion in Section 5.1 only makes things worse. The agreement with GHOP is stated plainly rather than buried, which I appreciate. On your decoherence worry: I'd let it go. The bound in eq. (71) sits some sixteen orders below 10^-11, so no plausible change in how coherence is modeled rescues the mechanism. The fragile step is elsewhere. The abstract's last sentence, that this rules out any mechanism without a new CP source, is not what Sections 4.3–4.4 show. Those sections compute one channel: reflection off a zero-thickness wall, perturbative in M, in 1+1 dimensions. The prose bridge in Section 5.2 says a CP-odd observable requires coherence over 1/m_q, but their own nonzero Δ contradicts that as stated; the defensible version is a power-counting suppression whose exponent depends on the minimum number of mass and flavor-changing insertions needed for a rephasing-invariant structure, and they never bound that number in general. Moderate, not fatal, and the quartet structure suggests the bound is at least as severe. Minor: eq. (62) carries ℓ^9 where eq. (63) carries ℓ^6 for the same quantity, and eq. (71) is quoted to one digit off hand-picked inputs (T = 100 GeV, M_W = T/2, J = 5×10^-5) with no uncertainty. For anyone working on electroweak baryogenesis or on CKM CP violation as a cosmological source, this is worth reading closely. Send it out; ask for the abstract claim to be narrowed to what was computed and the ℓ power fixed.

Referee report

Significance

If the result holds, it closes the CKM phase as a driver of electroweak baryogenesis and turns the baryon asymmetry into evidence for physics beyond the Standard Model. The paper's strengths are real and should be named: the calculation is fully analytic; the perturbative expansion is stated together with its validity condition Mℓ ≪ 1 (Section 4.2); the up-quark results are explicitly flagged as upper bounds because the top is far off shell (Section 4.4, eq. 71); two structurally different methods (Green's functions and the 'soap bubble' model) give the same power counting and comparable magnitudes; and the CP-odd structures are identified with basis-independent invariants, the Jarlskog determinant and the new D^d of eq. (61), each of which vanishes when two same-charge quarks are degenerate. The output is a specific, falsifiable number rather than a parametric estimate, and it independently corroborates a contemporaneous analysis. The main reservation is not the computation but the breadth of the exclusion drawn from it.

Major objections (4)

[Abstract, sentence 6; Section 5.2] The headline claim [abstract:s6] that 'the generality of our arguments rules out any mechanism of electroweak baryogenesis that does not make use of a new source of CP violation' is not what Sections 4.3–4.4 establish. Those sections compute one channel: quasiparticle reflection off a zero-thickness wall (eq. 2), in 1+1 dimensions, perturbatively in the quark-mass matrix, for the specific FS reflection mechanism. The generalization rests entirely on the prose of Section 5.2, which asserts that a CP-odd observable 'requires the quantum interference of amplitudes ... whose coherence persists over a time of at least 1/m_q,' while QCD limits coherence to ℓ ~ 1/(g_s^2 T). That sentence is contradicted by the paper's own result: Δ^d_9(ω) in eq. (66) is nonzero at m_b ℓ ≈ 0.04, i.e. precisely in the regime where coherence is shorter than 1/m_q. The correct general statement is a power-counting suppression whose exponent depends on the minimal number of mass and flavor-changing insertions needed to build a rephasing-invariant CP-odd structure, and the paper does not bound that number for mechanisms other than the one it computes. The authors should either supply that general power-counting argument (the quartet structure of the Jarlskog determinant suggests the bound is at least as severe as Δ_7, but this is not shown) or restrict the abstract and Section 5.2 to the class of scattering/reflection mechanisms actually analyzed.
[Eq. (4) and footnote 3] The master formula (4) is obtained from (3) by using T†_LL T_LL + R†_LR R_LR = 1 to eliminate the transmission terms. With an imaginary part in the self-energy this relation fails: flux is absorbed by the plasma, and the deficit carries baryon number that eq. (4) does not track. Footnote 3 addresses this in a single sentence ('Baryon number is still conserved throughout the scattering process'), which asserts conservation of the total but does not show that the absorbed component deposits its baryon number on the unbroken side, where by the Γ_out = ∞ assumption it is erased, rather than in the broken phase, where it would add to n_B. Since every subsequent number in the paper flows through eq. (4), the authors should either demonstrate that the neglected term is itself suppressed by powers of ℓ, or state explicitly the assumption under which it vanishes.
[Eqs. (62) and (63)] The two displayed forms of the up-quark contribution are dimensionally inconsistent with each other. Eq. (62) reads Δ^u_7(ω) = −16 f_7(6ℓ(ω−Ω0)) Im Tr[δp_L M δp_R M^3] ℓ^9, while eq. (63) gives the same quantity as 2(27α_W T/(32Ω0 M_W^2))^2 f_7(...) D^u ℓ^6. With δp_L, δp_R ~ mass and M ~ mass, the trace in (62) has dimension mass^6, so ℓ^9 leaves an overall mass^−3; the ℓ^6 in (63) is the dimensionally correct power and matches the O(ℓ^7) bookkeeping of eq. (58). Eq. (62) therefore appears to contain a typographical error in the exponent (and possibly in the prefactor −16 relative to eq. 63). This should be corrected, since the ℓ-power is the entire physical content of the suppression argument.
[Eq. (71) and Section 5.1] The quoted bound |n_B/s| < 6×10^−27 is presented as an upper bound, but its dominant ingredient, the up-quark term of eqs. (62)–(63), is derived from an expansion in Mℓ that the authors themselves state breaks down for the top quark (m_t ℓ ≈ 1, Section 4.2). The paper is commendably explicit that the up-quark result is qualitative and overestimates the contribution, but a bound derived from an uncontrolled expansion is not a bound. The authors should quantify the residual uncertainty, for instance by replacing the top-mass insertions with a resummed factor of order unity and quoting the resulting range, so that the reader can see how many orders of magnitude separate the result from 10^−11. Relatedly, eq. (71) is stated for the idealized zero-thickness wall of eq. (2) and the 1+1-dimensional reduction of Section 2.3; the thick-wall discussion at the end of Section 5.1 is qualitative (a power of ℓ/δ followed by a WKB factor exp(−kδ)). The bound should be labeled as applying to the idealized configuration, with the thick-wall statement flagged as an expectation rather than a result.

Minor objections (9)

[Eq. (73)] The displayed equation begins with a doubled equals sign ('ˆf9(x) = = 154{...}'), which should be corrected.
[Eq. (56)] There is a stray comma between 'det C ℓ^9' and the following sentence beginning 'The quantity det C'; the punctuation should be cleaned up.
[Section 4.3] Several typographical errors should be fixed: 'Refering' for 'Referring', 'the the charged Higgs' in the sentence after eq. (54), and 'broken broken phase' in Section 2.5.
[Section 5.1] The sentence describing the form factors ('The form factor peaks at a value of order one, and have a width of order the quasiparticle width, γ') has a subject-verb disagreement and should read 'has a width'.
[Reference [8]] The GHOP work is cited as a preprint (CERN 93/7081 and companion report numbers). Since the paper's agreement with GHOP is emphasized in the abstract, the citation status should be updated if a published version exists, or the comparison should be phrased so that it does not depend on an unpublished source.
[Figure 5] The caption gives the argument of f_7 and f_9 as (ω−Ω0)/γ = 6ℓ(ω−Ω0) but does not state the vertical normalization or the plotted range of x; adding these would make the figure self-contained.
[Section 2.5] The stability of the abnormal branch at small momentum is assumed from ref. [19]. It would help to state the momentum range over which this is taken to hold, since the relevant phase space is restricted to that region.
[Eq. (18)] The numerical estimate 10^−7 × Δ̄ should state the values of α_W and m_s/T used, so that the reader can reproduce the coefficient.
[Section 3.1, eq. (20)] The chain ℓ ≃ 1/T ≪ 1/p ≃ 1/δΩ ≃ 20/T should specify the temperature at which the numerical values are quoted (T = 100 GeV is used later in Section 5.1), since the inequalities are stated numerically.

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The paper

The paper claims

The quark-mixing phase cannot by itself generate the universe's baryon asymmetry: QCD collisions decohere the quasiparticles scattering off the electroweak bubble wall, suppressing the predicted asymmetry to a negligible level.

The reading

The paper asks whether the single CP-violating phase of the quark mixing matrix can produce the universe's baryon asymmetry during a first-order electroweak phase transition, as an earlier quasiparticle-reflection mechanism proposed. Its answer is no: the quarks and antiquarks scattering off the expanding bubble are quasiparticles whose QCD collisions destroy quantum coherence after a distance $�ell �sim 1/T$. The authors convert the damping rate $�gamma$ into a coherence length $�ell=1/(6�gamma)$, sum the paths by which a quasiparticle can flip chirality and flavor inside the bubble, and find each path suppressed by $�exp(-L/2�ell)$. The resulting reflection asymmetry is many orders of magnitude below what is needed, so the quark-mixing phase cannot be the sole CP source for electroweak baryogenesis.

What carries the argument

The load-bearing object is the quasiparticle coherence length $�ell=1/(6�gamma)$, with $�gamma$ the QCD damping rate. The paper replaces the sharp bubble wall by a damped propagation problem: left- and right-handed quasiparticles have complex momenta whose imaginary parts attenuate any amplitude as $�exp(-L/2�ell)$ over a path length $L$. It then builds a diagrammatic expansion for the reflection matrix in which each chirality flip comes from the quark mass matrix and each flavor change from charged-Higgs exchange in the plasma. The same physics is cross-checked with a 'soap bubble' model that replaces the bubble by an exponentially decaying mass profile $M e^{-z/�ell}$. The coherence length does the work of confining the calculation to a surface layer and of generating the powers of $M�ell$ and $�delta p�,�ell$ that suppress the asymmetry.

Extended reading notes

Core claim

The central claim is that QCD damping, interpreted as quantum decoherence, reduces the reflection asymmetry of the original mechanism to a negligible amount. Solving an effective Dirac equation with complex momenta $P_L$ and $P_R$ whose imaginary parts encode damping, the paper shows that only a thin outer layer of the bubble, of thickness $�ell$, contributes coherently to the reflected wave. The leading contributions to the left-right asymmetry $�Delta(�omega)$ appear at order $�ell^7$ and $�ell^9$ and are proportional to the standard CP-odd determinant $�det C$ and to an analogous invariant $D$; every quark-mass insertion or flavor-changing insertion brings a factor of $�ell$. Numerically the paper quotes $n_B/s < 6�times 10^{-27}$, to be compared with the observed $(4$--$6)�times 10^{-11}$. It concludes that total reflection of strange quarks, the ingredient the original estimate relied on, is impossible once damping is included, and that any electroweak baryogenesis mechanism using the quark-mixing phase alone is ruled out.

Load-bearing premise

The load-bearing premise is that the QCD damping rate $�gamma$ can be treated as a hard coherence length $�ell=1/(6�gamma)$ and that every amplitude is attenuated by $�exp(-L/2�ell)$ along its path; if off-diagonal quantum coherence survives longer than $1/�gamma$, the power counting and the numerical bound collapse.

Editorial extensions

If this is right

If the argument is right, the Standard Model's quark-mixing phase cannot be the origin of the baryon asymmetry, even in extensions that leave the light-quark sector unchanged; a new CP-violating source is required.
Only a layer of thickness $�ell$ at the bubble surface contributes to coherent reflection, so mechanisms that imagine quasiparticles probing the bubble interior over distances $1/m_q$ are excluded.
A realistic wall of thickness $10$--$100/T$ suppresses the asymmetry further, through the reduced mass increment over $�ell$ and a WKB factor for thick walls.
Top-quark-mediated mechanisms are not subject to the same suppression because $�ell m_t �simeq 1$, but they must introduce a new source of CP violation.
Two-Higgs-doublet and supersymmetric scenarios with new CP phases are left viable; the result narrows the target to those extensions.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

A useful extension is to treat the result as a constraint on new light-quark CP phases: any such phase must act through classical transport or through top quarks, not through coherent light-quark interference across the wall.
The analysis suggests a broader test: compare coherent and Boltzmann treatments of any wall-scattering baryogenesis model; where the two differ by powers of $m_q�ell$, the coherent treatment should be discarded.
A real-time lattice or spectral-function calculation of the quasiparticle width and off-diagonal density matrix would turn the assumed hard cutoff into a checkable input.
If the suppression holds, baryogenesis becomes a complementary probe of beyond-Standard-Model CP violation, alongside electric dipole moment searches.

Original abstract

We analyze the mechanism of electroweak baryogenesis proposed by Farrar and Shaposhnikov in which the phase of the CKM mixing matrix is the only source of $CP$ violation. This mechanism is based on a phase separation of baryons via the scattering of quasiparticles by the wall of an expanding bubble produced at the electroweak phase transition. In agreement with the recent work of Gavela, Hern\'andez, Orloff and P\`ene, we conclude that QCD damping effects reduce the asymmetry produced to a negligible amount. We interpret the damping as quantum decoherence. We compute the asymmetry analytically. Our analysis reflects the observation that only a thin, outer layer of the bubble contributes to the coherent scattering of the quasiparticles. The generality of our arguments rules out any mechanism of electroweak baryogenesis that does not make use of a new source of $CP$ violation.

The compiled record

The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Compiled by classifier-1.13-20260917 via OpenRouter, question bank abstract-p1-20260923, 2026-09-23: 1 request, 5,556 input tokens, $0.0002 reported.

What the abstract itself states, as probabilities: claims first 0.03 · states limitation 0.61 · human participants 0.01 · controlled comparison 0.04 · randomized assignment 0.01 · states quantitative result 0.12 · compares with prior results 0.90 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v1. Results and the main claim are underlined; show every role.

We analyze the mechanism of electroweak baryogenesis proposed by Farrar and Shaposhnikov in which the phase of the CKM mixing matrix is the only source of $CP$ violation. This mechanism is based on a phase separation of baryons via the scattering of quasiparticles by the wall of an expanding bubble produced at the electroweak phase transition. In agreement with the recent work of Gavela, Hern\'andez, Orloff and P\`ene, we conclude that QCD damping effects reduce the asymmetry produced to a negligible amount. We interpret the damping as quantum decoherence. We compute the asymmetry analytically. Our analysis reflects the observation that only a thin, outer layer of the bubble contributes to the coherent scattering of the quasiparticles. The generality of our arguments rules out any mechanism of electroweak baryogenesis that does not make use of a new source of $CP$ violation.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	We analyze the mechanism of electroweak baryogenesis proposed by Farrar and Shaposhnikov in which the phase of the CKM mixing matrix is the only source of $CP$ violation.	contribution 0.63	0.53	0.05	asserted 0.86
s1	This mechanism is based on a phase separation of baryons via the scattering of quasiparticles by the wall of an expanding bubble produced at the electroweak phase transition.	background 0.80	0.08	0.03	asserted 1.00
s2	In agreement with the recent work of Gavela, Hern\'andez, Orloff and P\`ene, we conclude that QCD damping effects reduce the asymmetry produced to a negligible amount.	result 1.00	0.69	0.69	asserted 0.99
s3	We interpret the damping as quantum decoherence.	interpretation 1.00	0.74	0.05	asserted 1.00
s4	We compute the asymmetry analytically.	method 0.85	0.95	0.04	asserted 1.00
s5	Our analysis reflects the observation that only a thin, outer layer of the bubble contributes to the coherent scattering of the quasiparticles.	interpretation 0.46	0.80	0.05	asserted 0.98
s6	The generality of our arguments rules out any mechanism of electroweak baryogenesis that does not make use of a new source of $CP$ violation.	interpretation 0.91	0.67	0.73	asserted 1.00

What kind of paper the classifier reports this is: theoretical result 1.00 · evidence from proof or derivation 0.99.

What was examined, and what was not

sources read

arXiv listing abstract v1

not examined

full text
figures and tables
references and citing sentences
relations to other papers

levels run

P abstract

not run

S sections
T body sentences
C citations
R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

Figures

**Figure 1.** Schematic picture of the dispersion relations for

**Figure 3.** a) Graph contributing to the real part of the quasip

**Figure 4.** First two terms in the expansion for the reflection m

**Figure 5.** The energy-dependent form factors f7 and f9, evaluated at (ω−Ω0)/γ = 6ℓ(ω− Ω0). Note that f9 is peaked at ω = Ω0 ≃ 50 GeV, while f7 vanishes there. 35

**Figure 6.** This loop summarizes all the contributions to ∆

Showing 5 of the paper's 6 figures. See all figures in the PDF ↗ Figures reproduced from arXiv:hep-ph/9404302 by the authors.

References

Works cited (24)

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A. D. Sakharov JETP Lett. 5 (1967) 24

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For a review of various attempts see A. G. Cohen, D. B. Kapl an and A. E. Nelson, Ann. Rev. Nucl. Part. Sci. , 43 (1993) 27. See also refs. [22, 23, 24]

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[7]

G. R. Farrar and M. E. Shaposhnikov, Phys. Rev. Lett. 70 (1993) 2833; preprint CERN-TH-6734/93, RU-93-11. 33

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[8]

M. B. Gavela, P. Hern´ andez, J. Orloﬀ and O. P` ene, prepri nt 1993, CERN 93/7081, LPTHE Orsay-93/48, HUTP-93/48, HD-THEP-93-45

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D. A. Kirzhnits and A. D. Linde, Phys. Lett. B 72 (1972) 471

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See for example J. Ambjorn, T. Askgaard, H. Porter and M. E. Shaposhnikov, Phys. Lett. B 244 (1990) 479; Nucl. Phys. B 353 (1991) 346

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A. A. Belavin, A. M. Polyakov, A. S. Schwartz and Yu. S. Ty upkin, Phys. Lett. B 59 (1975) 85. G. ’t Hooft, Phys. Rev. Lett. 37 (1976) 8; Phys. Rev. D 14 (1976) 3432

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M. Dine, P. Huet, R. Singleton, Jr. and L. Susskind, Phys. Lett. B 257 (1991) 351. 34 Figure Captions Figure 1. Schematic picture of the dispersion relations for a fermionic quasiparticle in a hot plasma. The upper curve represents the normal branch. Th e lower curve represents the abnormal branch, which corresponds to the pr opagation of a “hole.” The ab...

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Test of CP Invariance in vector-boson fusion production of the Higgs boson using the Optimal Observable method in the ditau decay channel with the ATLAS detector
hep-ex 2016-02 accept novelty 6.0 of 10

No CP violation is observed in Higgs boson couplings to electroweak gauge bosons in VBF production, giving the 68% CL constraint d~ in [-0.11, 0.05].
Two-Step Electroweak Baryogenesis
hep-ph 2015-08 conditional novelty 6.0 of 10

CP violation in a partially secluded singlet sector can generate the observed baryon asymmetry during the first step of a two-step electroweak phase transition while evading present and projected electric dipole momen...
Cutoff Scales in the Type-I 2HDM with Strongly First-Order Electroweak Phase Transitions: One-Step versus Multistep
hep-ph 2026-09 conditional novelty 5.0 of 10

In the Type-I 2HDM, one-step strongly first-order electroweak phase transitions limit the UV cutoff to O(10^6) GeV, whereas two-step transitions in the inverted scenario can reach cutoff scales up to 10^15 GeV without...
Electroweak Baryogenesis: Advances in Sphaleron Rate Calculations and Implications of Thermal Phase Transitions
hep-ph 2026-07 conditional novelty 5.0 of 10

Sphaleron rates can be computed gauge-invariantly in 3D thermal EFT, yielding a new baryon-washout criterion x = lambda3/g3^2 that replaces v_c/T_c > 1 for electroweak baryogenesis.
Intrinsic Properties of Large CP Violation in the Complex Two-Higgs-Doublet Model
hep-ph 2025-12 unverdicted novelty 5.0 of 10

Global scans of complex 2HDM show Type-I models maximize gauge CPV near light-Higgs degeneracy with high eEDM, Type-II suppress gauge CPV but permit large Yukawa CPV and low eEDM via cancellations, plus hidden CPV in ...
Baryogenesis from a dark first-order phase transition
hep-ph 2019-10 conditional novelty 5.0 of 10

A dark SU(2) sector with two Higgs doublets and a neutrino portal could generate the baryon asymmetry via a first-order phase transition, predicting ΔN_eff = 0.09-0.13 and exotic Higgs/Z decays, though the asymmetry y...
LHC-friendly minimal freeze-in models
hep-ph 2018-11 conditional novelty 5.0 of 10

Recasting four LHC long-lived-particle searches constrains minimal freeze-in dark matter models, excluding parent masses up to about 650 GeV for a lepton partner and 1.5 TeV for a quark partner at long lifetimes.
Electroweak Baryogenesis and the Standard Model Effective Field Theory
hep-ph 2017-10 accept novelty 5.0 of 10

Two effective-field-theory scenarios related by the classical equations of motion produce baryon asymmetries differing by a factor of four, so the Standard Model EFT expansion fails for electroweak baryogenesis.
Gauss-Bonnet Chern-Simons gravitational wave leptogenesis
hep-th 2017-02 conditional novelty 5.0 of 10

A Gauss-Bonnet coupling to the inflaton exponentially amplifies sub-horizon gravitational waves and enhances gravitational-anomaly leptogenesis, matching the observed baryon asymmetry for a UV cutoff near 10^14-16 GeV.
Electroweak Baryogenesis from Exotic Electroweak Symmetry Breaking
hep-ph 2015-04 conditional novelty 5.0 of 10

A two-stage electroweak phase transition, with baryogenesis occurring in an exotic scalar transition before the standard Higgs vacuum forms, is realizable in an inert two-Higgs-doublet model provided a singlet raises ...
Singlet Fermionic Dark Matter and the Electroweak Phase Transition
hep-ph 2013-05 conditional novelty 5.0 of 10

A singlet fermion plus a Z2-breaking singlet scalar can, in a broad scanned region, account for all dark matter and produce a strongly first-order electroweak phase transition while evading current direct detection an...
Lattice QCD calculation of the pion-nucleon coupling $\bar{g}_0$ induced by the QCD $\Theta$-term
hep-lat 2026-09 accept novelty 4.0 of 10

A precise determination of the CP-violating pion-nucleon coupling from the isovector scalar charge yields gbar0/(2Fpi) = 17.4(1.9)x10^{-3} Theta.
Revisiting Singlet Fermion Dark Matter with a Scalar Portal: Connecting Higgs Phenomenology and Strong Electroweak Phase Transition
hep-ph 2026-01 conditional novelty 4.0 of 10

In a no-VEV singlet scalar + singlet fermion dark matter extension of the SM, a strong first-order electroweak phase transition, the observed dark matter relic density, and collider/direct-detection constraints can co...
Test of CP invariance in vector-boson fusion production of the Higgs boson in the $H\rightarrow\tau\tau$ channel in proton$-$proton collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector
hep-ex 2020-02 accept novelty 4.0 of 10

No CP violation is observed in vector-boson-fusion Higgs production with H to tau tau decays, and the CP-odd coupling parameter is constrained to [-0.090, 0.035] at 68% confidence, consistent with the Standard Model.
Why is there more matter than antimatter? Calculational methods for leptogenesis and electroweak baryogenesis
hep-ph 2018-12 conditional novelty 4.0 of 10

The paper reviews and demonstrates a closed time-path scheme for deriving fluid equations of leptogenesis and electroweak baryogenesis, including a new mixing source term at phase boundaries.
Electroweak baryogenesis
hep-ph 2012-06 accept novelty 3.0 of 10

Electroweak baryogenesis requires new TeV-scale particles that make the electroweak phase transition strongly first order and supply CP violation, and this review argues those requirements make the scenario testable b...
Chern-Simons Modified General Relativity
hep-th 2009-07 conditional novelty 3.0 of 10

Chern-Simons modified gravity, a parity-violating extension of general relativity, is motivated by three independent derivations and is already bounded by binary pulsar timing at roughly 10^-9 km in the canonical Cher...
Towards triggerless four-dimensional detectors for High Energy Physics collider experiments
physics.ins-det 2026-07 unverdicted novelty 2.0 of 10

Reviews precision timing integration in LHC upgrades and discusses a possible shift to triggerless detectors enabled by timing and networking, with reflections on physics benefits.
Electric dipole moments and the search for new physics
hep-ph 2022-03 accept novelty 2.0 of 10

A broad consortium argues that complementary electron, neutron, atomic, molecular and storage-ring EDM measurements, tied together by lattice QCD and effective field theory, are needed to identify the source of CP vio...

How later papers used it

137 later papers cite it

Evidence: some. 137 of the citing papers share no author with it, and 10 of those carry a confident label from Pith's citation classifier.

Pith read 7 of the 165 citing sentences, choosing only those whose citation markers point at this paper alone, and wrote the paraphrases from them. The summary, the counts, the evidence level, the links and the quotes come from code; the summary counts the papers listed below. A later paper is listed under a label when Pith's citation classifier gives one of its sentences that label at probability 0.8 or more (0.95 for support), Pith's reading finds that the citing paper itself did it, and a second check confirms the paraphrase against the sentence. This section lists uses only. It does not list criticism or disagreement, so their absence here says nothing about how the paper has been received. Papers that share an author with this one are listed apart, under "By the same authors". A quote is the citing authors' own sentence, shown when their paper's licence is CC BY, CC BY-SA or CC0. JSON

2 later papers by other authors are listed below: 2 used its method or tool.

Uses its method or tool 2 of 3 papers with this label

Used the techniques developed in this paper for electroweak baryogenesis to consider the amplitude of the χ1ℓ transition to χ2ℓ̅.

Leptogenesis via Varying Weinberg Operator: a Semi-Classical Approach (2018) · 0.99 · paraphrased: the licence does not allow quoting
[ref] , we iteratively solve the Dirac equation [ref] when the Dirac mass term $ℳ$ is smaller than the damping rate.

Electroweak-like Baryogenesis with New Chiral Matter (2021) · Perturbative regime ((i)-(A)) · 1.00

How the literature uses it

129 arXiv papers cite this in 157 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 117 sentences without a confident label

Uses its method or tool 3 papers

We closely follow the techniques presented in [ref] .

The minimal fermionic model of electroweak baryogenesis · The baryon asymmetry: an analytic estimate · 1.00
The resultant reflection matrix $R_ℓ$, corresponding to the reflection matrix $R̅_LR$ in [ref] , is R_ℓ(z_0) = i ∫_0^+∞ dz_1 e^-z_1/L e^ i k_out z_1 M^†_ℓ (z_0+z_1) e^-i k_in z_1 .

Leptogenesis via Varying Weinberg Operator: a Semi-Classical Approach · Lepton asymmetry in the semi-classical approximation · 0.89
[ref] , we iteratively solve the Dirac equation [ref] when the Dirac mass term $ℳ$ is smaller than the damping rate.

Electroweak-like Baryogenesis with New Chiral Matter · Perturbative regime ((i)-(A)) · 1.00

Cites it as support 5 papers

Furthermore, even if the phase transition is a SFOPT, the resulting baryon asymmetry from the EWBG in the minimal SM has been found to be much smaller than the observed value due to the tiny Yukawa couplings of quarks and the CKM mixing [ref] .

ALP-Assisted Strong First-Order Electroweak Phase Transition and Baryogenesis · Introduction · 0.96
And most relevantly for this review, the amount of matter-antimatter asymmetry allowed in the Standard Model is fundamentally insufficient to explain the observed matter-antimatter asymmetry of the universe [ref] .

Quark flavour physics: status and future prospects · Introduction · 0.98
First, for a 125 GeV Higgs boson, the electroweak phase transition is a smooth crossover [ref] , failing to provide the required departure from thermal equilibrium.

Intrinsic Properties of Large CP Violation in the Complex Two-Higgs-Doublet Model · Introduction · 0.96

Cites it as background 22 papers

The VIA-method made its first appearance in [ref] .

CP-violating transport theory for Electroweak Baryogenesis with thermal corrections · Introduction · 0.96
Electroweak baryogenesis requires two ingredients that go beyond the SM: * New sources of $CP$ violation [ref] ; * Modification of the EWPT such that it is strongly first order (rather than a smooth crossover, as is the case in the SM [ref] ).

$CP$ violation from $\tau$, $t$ and $b$ dimension-6 Yukawa couplings -- interplay of baryogenesis, EDM and Higgs physics · The baryon asymmetry $Y_B$ · 0.87
Two commonly used frameworks have been developed to formulate the transport equation: the semi-classical approach under the WKB approximation [ref] , and the VEV-insertion approximation (VIA) method [ref] .

The Discriminant Power of Bubble Wall Velocities: Gravitational Waves and Electroweak Baryogenesis · $v_w$-Dependence of Baryon Number Generation · 0.90

Discussion

Disagree with the review, or know something it missed? Leave a comment, highlight any passage above to comment on it, or challenge this review formally.

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