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Energy counterexample


Statement and scope

Proved. There are finite systems of distinct singleton moduli, with the original activation rule, and cutoffs Q→∞Q\to\infty such that

E:=∑qeqlog⁡q⟶2log⁡2,HB(Q)−βHQ∼(log⁡Q)1/21⟶∞.(1)\mathcal E:=\sum_q e_q\log q\longrightarrow2\log2, \qquad H_B(Q)-\beta H_Q\sim(\log Q)^{1/21}\longrightarrow\infty. \tag{1}

Here BB is the delayed excluded union, β\beta is the full periodic union measure, and eqe_q are the full first-kill measures in increasing modulus order. All the moduli are at most QQ.

Consequently there is no absolute CC for which

HB(X)≤βH⌊X⌋+C(1+∑q≤Xeqlog⁡q)(2)H_B(X)\le\beta H_{\lfloor X\rfloor} +C\left(1+\sum_{q\le X}e_q\log q\right) \tag{2}

holds for every finite distinct-modulus singleton system. This accounts for the entire preparatory sieve, not just the late first-kill cells. The construction also refutes a uniform additive O(log⁡log⁡X)O(\log\log X) error and the proposed rank-sensitive error Cr=exp⁡(o(r))C_r=\exp(o(r)).

This is not an infinite counterexample to Problem 25. Its normalized harmonic excess tends to zero. A uniform additive o(log⁡X)o(\log X) estimate and the constant first-kill entropy bound remain open.

The rank-filtered refinement below increases the attainable lower-bound exponent to every γ<(7 21/7−3 31/3−3)/4=0.100469…\gamma<(7\,2^{1/7}-3\,3^{1/3}-3)/4=0.100469\ldots, still with energy tending to 2log⁡22\log2. It does not contradict the weaker square-root energy target.

A sparse divisor-residue channel

Let L=2kL=2^k and Q>LQ>L be integers. For each odd residue r∈{1,…,L−1}r\in\{1,\ldots,L-1\}, put

Dr={q∈N:L<q≤Q, q≡r(modL)},br=μ(⋃q∈DrqZ^).D_r=\{q\in\mathbb N:L<q\le Q,\ q\equiv r\pmod L\}, \qquad b_r=\mu\left(\bigcup_{q\in D_r}q\widehat{\mathbb Z}\right).

We claim that some such rr satisfies

br≪L−1/2(log⁡(2Q))2−1.(3)b_r\ll L^{-1/2}(\log(2Q))^{\sqrt2-1}. \tag{3}

The implied constant is absolute.

For every odd prime p≤Qp\le Q, independently choose a nonnegative integer VpV_p with

Pr⁡(Vp=v)=(1−1/p)p−v,M=∏p≤Qp≠2pVp.\Pr(V_p=v)=(1-1/p)p^{-v}, \qquad M=\prod_{\substack{p\le Q\\p\ne2}}p^{V_p}.

These are precisely the finite-dimensional Haar valuation laws. Every q∈Drq\in D_r is odd and has all prime factors at most QQ, so

br=Pr⁡(∃q∈Dr:q∣M).b_r=\Pr(\exists q\in D_r:q\mid M).

For each realization of MM, at most min⁡(φ(L),τ(M))\min(\varphi(L),\tau(M)) unit residues modulo LL occur among its divisors in (L,Q](L,Q]. Here τ\tau is the number of positive divisors. Consequently

1φ(L)∑r odd mod Lbr≤Emin⁡(1,τ(M)φ(L))≤φ(L)−1/2Eτ(M).(4)\frac1{\varphi(L)}\sum_{r\text{ odd}\bmod L}b_r \le\mathbb E\min\left(1,\frac{\tau(M)}{\varphi(L)}\right) \le\varphi(L)^{-1/2}\mathbb E\sqrt{\tau(M)}. \tag{4}

The divisor moment factors over the independent valuations. For p≥3p\ge3,

(1−1/p)∑v≥0v+1 p−v=1+2−1p+O(p−2).(1-1/p)\sum_{v\ge0}\sqrt{v+1}\,p^{-v} =1+\frac{\sqrt2-1}{p}+O(p^{-2}).

The remainder is bounded uniformly in pp: the terms v≥2v\ge2 have sum O(p−2)O(p^{-2}). Comparison with the local factors of ∏p≤Q(1−1/p)−(2−1)\prod_{p\le Q}(1-1/p)^{-(\sqrt2-1)} therefore gives

Eτ(M)≪∏p≤Q(1−1/p)−(2−1)≪(log⁡(2Q))2−1.(5)\mathbb E\sqrt{\tau(M)} \ll\prod_{p\le Q}(1-1/p)^{-(\sqrt2-1)} \ll(\log(2Q))^{\sqrt2-1}. \tag{5}

The last bound is the elementary Euler-product estimate proved in coprime entropy. Equations (4)--(5), together with φ(L)=L/2\varphi(L)=L/2, prove (3). No distribution theorem for primes in arithmetic progressions is used.

From now on choose

Q=⌊exp⁡(L21/20)⌋Q=\left\lfloor\exp(L^{21/20})\right\rfloor

and choose the least odd rr minimizing brb_r. This is a finite, deterministic choice: each brb_r is the exact proportion of covered residues in a finite common period. The minimum satisfies (3). Since 2−1<5/12\sqrt2-1<5/12, we obtain

br≪L−1/2+(21/20)(5/12)=L−1/16.(6)b_r\ll L^{-1/2+(21/20)(5/12)}=L^{-1/16}. \tag{6}

The finite congruence system

First install the kk classes

Cj=[2j−1−1]2j,1≤j≤k.(7)C_j=[2^{j-1}-1]_{2^j},\qquad1\le j\le k. \tag{7}

These are disjoint full cylinders: membership is equivalent to v2(n+1)=j−1v_2(n+1)=j-1. Their full survivor set is the single fiber [−1]L[-1]_L, of measure 1/L1/L.

Set

α=L−1−r∈[0,L−2],\alpha=L-1-r\in[0,L-2],

and then install one class

[α]q(q∈Dr).(8)[\alpha]_q\qquad(q\in D_r). \tag{8}

All new moduli are odd and greater than LL, whereas the old moduli are the distinct powers of two at most LL. Thus all moduli are globally distinct and all old classes precede the new ones in increasing modulus order. The residues in both (7) and (8) are normalized; in particular 0≤α<q0\le\alpha<q for every new class.

The full union in (8) is the common translate by α\alpha of the multiples union generated by DrD_r, hence has measure brb_r. Because all its moduli are odd, this event is independent of the 2-adic fiber [−1]L[-1]_L. The final full survivor measure is therefore exactly

δ=1−β=1−brL.(9)\delta=1-\beta=\frac{1-b_r}{L}. \tag{9}

Exact delayed survivors and activation

The positive roots omitted by the delayed versions of the old classes are

2h−1,1≤h≤k−1.2^h-1,\qquad1\le h\le k-1.

They are not covered by another old class, since the full old cylinders are disjoint. Every new modulus exceeds LL, so no new class is active at these roots. The remaining old delayed survivors are the positive integers in [−1]L[-1]_L.

The first positive point of this fiber is L−1L-1. For every later one, write

n=Lt+L−1,t≥1.n=Lt+L-1,\qquad t\ge1.

If n≤Qn\le Q, then

q=n−α=Lt+rq=n-\alpha=Lt+r

satisfies L<q≤n≤QL<q\le n\le Q and q≡r(modL)q\equiv r\pmod L, so q∈Drq\in D_r. Moreover n=q+αn=q+\alpha is precisely the first active endpoint of its new class. This checks activation without any change of cutoff or delay convention.

Thus the delayed survivor set AA satisfies the exact identity

A∩[1,Q]={2h−1:1≤h≤k},HA(Q)=∑h=1k12h−1<2.(10)A\cap[1,Q]=\{2^h-1:1\le h\le k\}, \qquad H_A(Q)=\sum_{h=1}^k\frac1{2^h-1}<2. \tag{10}

Bounded total first-kill energy

Since the old full cylinders are disjoint, their first-kill measures are 2−j2^{-j}. Their energy is

Eold=log⁡2∑j=1kj2j=(2−k+2L)log⁡2.(11)\mathcal E_{\mathrm{old}} =\log2\sum_{j=1}^k\frac{j}{2^j} =\left(2-\frac{k+2}{L}\right)\log2. \tag{11}

The sum of all the new first-kill measures is exactly the increment in full union measure, namely br/Lb_r/L. All new moduli are at most QQ, so (6) gives

0≤Enew≤brLlog⁡Q≪L−1/16+1/20=L−1/80.(12)0\le\mathcal E_{\mathrm{new}} \le\frac{b_r}{L}\log Q \ll L^{-1/16+1/20}=L^{-1/80}. \tag{12}

Together (11)--(12) prove E→2log⁡2\mathcal E\to2\log2.

On the other hand, (9)--(10) give

HB(Q)−βHQ=δHQ−HA(Q)≥(1−br)L1/20−2,(13)\begin{aligned} H_B(Q)-\beta H_Q &=\delta H_Q-H_A(Q)\\ &\ge(1-b_r)L^{1/20}-2, \end{aligned} \tag{13}

because HQ≥log⁡(Q+1)>L21/20H_Q\ge\log(Q+1)>L^{21/20}. In fact, using HQ=log⁡Q+O(1)H_Q=\log Q+O(1) and br=o(1)b_r=o(1), this excess is

(1+o(1))L1/20=(1+o(1))(log⁡Q)1/21.(14)(1+o(1))L^{1/20} =(1+o(1))(\log Q)^{1/21}. \tag{14}

This proves (1), disproves (2), and disproves a uniform additive O(log⁡log⁡X)O(\log\log X) error.

Consequence for the rank-sensitive target

The later prime-only amplification supersedes the rank-constant obstruction in this section: no finite rank-only additive bound exists, already at rank one. The construction here still has the distinct additional feature of bounded first-kill energy, and the calculations below remain valid.

The proved rank truncation in rank and moment obstructions states that, with

R=⌈8log⁡log⁡(3Q)⌉,R=\left\lceil8\log\log(3Q)\right\rceil,

the union B>RB_{>R} of classes whose moduli have Ω(q)>R\Omega(q)>R has HB>R(Q)=O(1)H_{B_{>R}}(Q)=O(1), uniformly over finite singleton families. Explicitly its bound is

HB>R(Q)≪(3/2)−R(log⁡(3Q))5/2=O(1).H_{B_{>R}}(Q) \ll(3/2)^{-R}(\log(3Q))^{5/2}=O(1).

Delete those high-rank classes from the construction and write B≤RB_{\le R} and β≤R\beta_{\le R} for the remaining delayed union and full union measure. Removing classes can only decrease Haar measure, and loses at most O(1)O(1) harmonic mass. Consequently

HB≤R(Q)−β≤RHQ≥HB(Q)−βHQ−O(1)≫L1/20.(15)H_{B_{\le R}}(Q)-\beta_{\le R}H_Q \ge H_B(Q)-\beta H_Q-O(1) \gg L^{1/20}. \tag{15}

Since R=(42/5)log⁡L+O(1)R=(42/5)\log L+O(1), any universal bounds

HB(X)≤βH⌊X⌋+CRfor all systems with Ω(q)≤RH_B(X)\le\beta H_{\lfloor X\rfloor}+C_R \quad\text{for all systems with }\Omega(q)\le R

must therefore satisfy, along this sequence,

CR≥exp⁡((1/168+o(1))R).(16)C_R\ge\exp\bigl((1/168+o(1))R\bigr). \tag{16}

In particular CR=exp⁡(o(R))C_R=\exp(o(R)) is impossible. This does not contradict the bounded-rank natural-density theorem, which does not assert such a uniform additive error.

Why this does not resolve Problem 25

The normalized excess is

HB(Q)−βHQHQ=1−brL−HA(Q)HQ∼1L⟶0.\frac{H_B(Q)-\beta H_Q}{H_Q} =\frac{1-b_r}{L}-\frac{H_A(Q)}{H_Q} \sim\frac1L\longrightarrow0.

Thus these finite systems do not produce a fixed positive logarithmic excess. Also, combining gadgets while retaining their preparatory classes for unbounded kk retains every class in (7). Those classes already have full Haar union measure one; their delayed survivor set is contained in {2h−1:h≥1}\{2^h-1:h\ge1\} and has natural density zero. Any additional deletions preserve that zero density. This direct combination therefore cannot give the required infinite counterexample.

The spectral conductor-energy inequality remains valid. What fails is its proposed uniform conversion to harmonic discrepancy. Neither a uniform additive o(log⁡X)o(\log X) bound nor the constant first-kill entropy target is refuted by this construction.

Two linear entropy charges also fail

The same example refutes linear charging of the unnormalized first-kill relative entropy either by the reciprocal sum or by the first-kill energy. This does not refute the constant normalized entropy target.

Let II index the new odd-modulus classes, and put ci=HEi(Q)/HQc_i=H_{E_i}(Q)/H_Q. Their exact endpoint deletion gives

m:=∑i∈IHEi(Q)=log⁡Q−log⁡L+O(1)L∼HQL,∑i∈Iei=brL.m:=\sum_{i\in I}H_{E_i}(Q) =\frac{\log Q-\log L+O(1)}L\sim\frac{H_Q}{L}, \qquad \sum_{i\in I}e_i=\frac{b_r}{L}.

The log-sum inequality, together with br≪L−1/16b_r\ll L^{-1/16}, yields

HQ∑icilog⁡+(ci/ei)≥mlog⁡mLHQbr≫L1/20log⁡L.(17)\begin{aligned} H_Q\sum_i c_i\log_+(c_i/e_i) &\ge m\log\frac{mL}{H_Qb_r}\\ &\gg L^{1/20}\log L. \end{aligned} \tag{17}

On the other hand, summing along the single residue channel gives

∑i1qi≍1+log⁡QL≍L1/20,\sum_i\frac1{q_i}\asymp 1+\frac{\log Q}{L} \asymp L^{1/20},

while (11)--(12) show ∑ieilog⁡qi→2log⁡2\sum_i e_i\log q_i\to2\log2. Thus neither of these costs can bound (17) up to an absolute linear factor, even after adding an absolute constant. The lower bound after normalization by HQH_Q is only ≫(log⁡L)/L\gg(\log L)/L, which tends to zero; it remains compatible with a universal bound for ∑icilog⁡+(ci/ei)\sum_i c_i\log_+(c_i/e_i).

Optimizing the divisor moment

The exponent 1/211/21 can be slightly improved without changing the construction. For every fixed 0<θ<10<\theta<1, replace the square root in (4) by the θ\thetath power. The local factors are

(1−1/p)∑v≥0(v+1)θp−v=1+(2θ−1)/p+Oθ(p−2),(1-1/p)\sum_{v\ge0}(v+1)^\theta p^{-v} =1+(2^\theta-1)/p+O_\theta(p^{-2}),

so the same proof gives

br≪θL−θ(log⁡(2Q))2θ−1.b_r\ll_\theta L^{-\theta}(\log(2Q))^{2^\theta-1}.

Choose Q=⌊exp⁡(La)⌋Q=\lfloor\exp(L^a)\rfloor with a>1a>1. The new energy is then at most a constant times

La2θ−θ−1.L^{a2^\theta-\theta-1}.

It tends to zero if a<(1+θ)/2θa<(1+\theta)/2^\theta, while the harmonic excess is asymptotic to La−1L^{a-1}. Elementary differentiation gives

max⁡0<θ<11+θ2θ=2elog⁡2,θmax=1log⁡2−1.\max_{0<\theta<1}\frac{1+\theta}{2^\theta} =\frac{2}{e\log2},\qquad \theta_{\rm max}=\frac1{\log2}-1.

Thus for every fixed

0<γ<1−elog⁡220<\gamma<1-\frac{e\log2}{2}

there are systems with E→2log⁡2\mathcal E\to2\log2 and excess ≍(log⁡Q)γ\asymp(\log Q)^\gamma. All activation and distinctness checks are unchanged. This remains sublogarithmic and does not give an infinite counterexample. The prepared-block entropy bound also shows that this mechanism's normalized entropy is small, even after optimizing its parameters.

Rank-filtered residue channels

Theorem. For every

0<γ<γ∗:=7 21/7−3 31/3−34=0.100469471…,(18)0<\gamma<\gamma_*:= \frac{7\,2^{1/7}-3\,3^{1/3}-3}{4} =0.100469471\ldots, \tag{18}

there are finite distinct-singleton systems with cutoffs Q→∞Q\to\infty and original activation such that

E⟶2log⁡2,HB(Q)−βHQ≥(log⁡Q)γ.(19)\mathcal E\longrightarrow2\log2,\qquad H_B(Q)-\beta H_Q\ge(\log Q)^\gamma. \tag{19}

Only a lower bound for the excess is claimed here, unlike the asymptotic equivalence in (1).

Write L=2kL=2^k, H=log⁡QH=\log Q, and fix c>1c>1, to be chosen below. Put

R=⌊clog⁡H⌋,I(c)=clog⁡c−c+1.R=\lfloor c\log H\rfloor,\qquad I(c)=c\log c-c+1.

For each odd residue r(modL)r\pmod L, define

Dr={q:L<q≤Q−L, q≡r(modL), Ω(q)≥R},br=μ(M(Dr)),mr=∑q∈Dr1q.(20)D_r=\{q:L<q\le Q-L,\ q\equiv r\pmod L,\ \Omega(q)\ge R\}, \quad b_r=\mu(M(D_r)),\quad m_r=\sum_{q\in D_r}\frac1q. \tag{20}

We choose QQ so that log⁡L/log⁡H\log L/\log H tends to a fixed positive constant. All estimates below are in this regime.

The rank-sensitive divisor moment

Let VpV_p, for odd primes p≤Qp\le Q, have the Haar geometric laws, and set M=∏3≤p≤QpVpM=\prod_{3\le p\le Q}p^{V_p}. The number NR(M)N_R(M) of divisors of MM with Ω≥R\Omega\ge R satisfies

NR(M)≤2−R∑d∣M2Ω(d)=2−R∏3≤p≤Q(2Vp+1−1).N_R(M)\le2^{-R}\sum_{d\mid M}2^{\Omega(d)} =2^{-R}\prod_{3\le p\le Q}(2^{V_p+1}-1).

At most min⁡(φ(L),NR(M))\min(\varphi(L),N_R(M)) odd channels in (20) can be represented among its divisors. Therefore

1φ(L)∑rbr≤φ(L)−1/3ENR(M)1/3≪L−1/3HA,A=31/3−1−clog⁡23.(21)\frac1{\varphi(L)}\sum_r b_r \le\varphi(L)^{-1/3}\mathbb E N_R(M)^{1/3} \ll L^{-1/3}H^A,\qquad A=3^{1/3}-1-\frac{c\log2}{3}. \tag{21}

For the last estimate, independence and the uniform local expansion give

(1−1/p)∑v≥0(2v+1−1)1/3p−v=1+31/3−1p+O(p−2).(1-1/p)\sum_{v\ge0}(2^{v+1}-1)^{1/3}p^{-v} =1+\frac{3^{1/3}-1}{p}+O(p^{-2}).

The remainder is uniform for p≥3p\ge3, since 21/3<32^{1/3}<3. The elementary Euler-product bound then gives the power H31/3−1H^{3^{1/3}-1}; the factor 2−R/32^{-R/3} supplies the remaining term in AA.

Enough channels retain reciprocal mass

Set Y=(Q−L)1/RY=(Q-L)^{1/R} and

S=∑R2<p≤Y1p=log⁡H−O(log⁡log⁡H).S=\sum_{R^2<p\le Y}\frac1p=\log H-O(\log\log H).

The last equality follows from ∑p≤x1/p=log⁡log⁡x+O(1)\sum_{p\le x}1/p=\log\log x+O(1), itself a consequence of the two-sided elementary Euler-product estimates used earlier. Products of RR distinct primes from this interval are odd, at most Q−LQ-L, and greater than LL: their minimum logarithm is greater than 2Rlog⁡R2R\log R, whereas log⁡L=O(log⁡H)\log L=O(\log H).

Sampling RR primes independently with weights 1/(pS)1/(pS), the collision probability is at most

(R2)S−2∑p>R2p−2=O(S−2)=o(1).{R\choose2}S^{-2}\sum_{p>R^2}p^{-2}=O(S^{-2})=o(1).

Unique factorization therefore gives

∑rmr≥(1−o(1))SRR!=H1−I(c)+o(1).(22)\sum_r m_r\ge(1-o(1))\frac{S^R}{R!} =H^{1-I(c)+o(1)}. \tag{22}

No prime distribution in residue classes is used here.

For definiteness let s=SR/(2R!)s=S^R/(2R!), so (22) is at least ss for all sufficiently large QQ. Define G={r:mr≥s/L}\mathcal G=\{r:m_r\ge s/L\}. The other channels contribute at most s/2s/2, because there are L/2L/2 odd channels. Uniformly mr≤CH/Lm_r\le CH/L, by summing the progression r+tLr+tL, t≥1t\ge1. Hence

∣G∣≫Ls/H=LH−I(c)+o(1).|\mathcal G|\gg Ls/H=L H^{-I(c)+o(1)}.

Choose the least-footprint channel in G\mathcal G. Equation (21) then proves the simultaneous estimates

mr≥H1−I(c)+o(1)L,br≪L−1/3HA+I(c)+o(1).(23)m_r\ge \frac{H^{1-I(c)+o(1)}}L,\qquad b_r\ll L^{-1/3}H^{A+I(c)+o(1)}. \tag{23}

The extra HI(c)+o(1)H^{I(c)+o(1)} in the footprint is the cost of restricting to large-mass channels; it is not discarded.

Installing the filtered channel

Use the binary preparation (7), leaving the full fiber [−1]L[-1]_L, and put α=L−1−r∈[0,L−2]\alpha=L-1-r\in[0,L-2]. Append [α]q[\alpha]_q for q∈Drq\in D_r. All new moduli are odd and exceed the old moduli. They are distinct, and every residue is normalized. Each distinct endpoint

n=q+α≤Qn=q+\alpha\le Q

lies in the old survivor fiber and is active at its own modulus. Its reciprocal mass, summed over DrD_r, is

∑q∈Dr1q+α=mr−O(1/L);\sum_{q\in D_r}\frac1{q+\alpha}=m_r-O(1/L);

indeed ∑q>L, q≡r (L)α/q2=O(1/L)\sum_{q>L,\ q\equiv r\ (L)}\alpha/q^2=O(1/L). Other appended congruences may also cover these points, which only helps the union count.

The new union has density brb_r on the odd-prime coordinates and is independent of the binary fiber. Thus its incremental measure is br/Lb_r/L, and its entire first-kill energy is at most

Enew≤brH/L.(24)\mathcal E_{\rm new}\le b_rH/L. \tag{24}

The old energy tends to 2log⁡22\log2. Its delayed survivor harmonic mass is at most HQ/L+3H_Q/L+3: the progression [−1]L[-1]_L costs at most HQ/L+1H_Q/L+1, and the inactive roots 2j−12^j-1 cost less than two. Its harmonic discrepancy is consequently at least −3-3. It follows that the final discrepancy is at least

−3+mr−O(1/L)−brHQL.(25)-3+m_r-O(1/L)-\frac{b_rH_Q}{L}. \tag{25}

Choose a fixed η>0\eta>0 and Q=⌊exp⁡(L1/η)⌋Q=\lfloor\exp(L^{1/\eta})\rfloor. Then L=Hη+o(1)L=H^{\eta+o(1)}. By (23)--(24), the new energy tends to zero if

η>ηcrit(c):=34(1+A+I(c))=3 31/3−clog⁡2+3I(c)4.(26)\eta>\eta_{\rm crit}(c):=\frac34(1+A+I(c)) =\frac{3\,3^{1/3}-c\log2+3I(c)}4. \tag{26}

Under this condition, (23) and (25) give an excess lower bound H1−I(c)−η+o(1)−O(1)H^{1-I(c)-\eta+o(1)}-O(1). The supremum of its exponent allowed by (26) is

1−I(c)−ηcrit(c)=4−3 31/3+clog⁡2−7I(c)4.1-I(c)-\eta_{\rm crit}(c) =\frac{4-3\,3^{1/3}+c\log2-7I(c)}4.

This expression is maximized at c=21/7c=2^{1/7}, since its derivative has the sign of log⁡2−7log⁡c\log2-7\log c. Substitution gives (18). For every smaller γ\gamma, choose η\eta with strict margins in (26) and 1−I(c)−η>γ1-I(c)-\eta>\gamma. This proves (19).

The examples do not refute the square-root energy estimate. For these parameters η>1/2\eta>1/2, while the trivial upper bound for positive excess is

(HB(Q)−βHQ)+≤(1−β)HQ≤HQ/L=H1−η+o(1)=o(H).(H_B(Q)-\beta H_Q)_+\le(1-\beta)H_Q\le H_Q/L =H^{1-\eta+o(1)}=o(\sqrt H).

Nor do these finite systems produce positive normalized logarithmic excess. The general conditioned-tail and square-root estimates remain unresolved.

One fixed family can have finite energy and unbounded additive excess

Proposition. There is one infinite distinct-singleton system whose delayed excluded union BB, full Haar union measure β\beta, and increasing-order first-kill masses eqe_q satisfy

d(B)=β<14,∑qeqlog⁡q<∞,lim sup⁡X→∞(HB(X)−βHX)=∞.(27)d(B)=\beta<\frac14,\qquad \sum_q e_q\log q<\infty,\qquad \limsup_{X\to\infty}(H_B(X)-\beta H_X)=\infty. \tag{27}

Its survivor set has natural density 1−β>3/41-\beta>3/4, so this is not a counterexample to Problem 25. It rules out bounded additive amortization even for one fixed family of finite total energy; it does not rule out the required o(log⁡X)o(\log X) bound.

The finite input is the proved construction (1): for some absolute C∗C_*, every T>0T>0 admits a finite singleton family F\mathcal F, all of whose moduli are at most a cutoff XX, with

E(F)≤C∗,DF(X):=HBF(X)−βFHX>T.(28)\mathcal E(\mathcal F)\le C_*,\qquad D_{\mathcal F}(X):=H_{B_{\mathcal F}}(X) -\beta_{\mathcal F}H_X>T. \tag{28}

Only this established finite input is needed below.

The exact affine lift

Let an already installed finite system have full union UoldU_{\rm old} of measure less than one and common period PP. Choose a surviving residue b∈[0,P)b\in[0,P), and let LL be a multiple of PP. Replace every class a(modq)a\pmod q in a fresh finite family by

La+b(modLq).(29)La+b\pmod{Lq}. \tag{29}

This residue is normalized, and the lifted full union lies in [b]L[b]_L, hence avoids UoldU_{\rm old}. Its actual delayed union is exactly LBF+bLB_{\mathcal F}+b: since 0≤b<L0\le b<L, the inequality Ln+b≥LqLn+b\ge Lq is equivalent to n≥qn\ge q.

The lifted footprint is βF/L\beta_{\mathcal F}/L. If all lifted moduli follow the old ones, its first-kill masses are eq/Le_q/L, so its energy contribution is

E(F)+βFlog⁡LL≤C∗+log⁡LL.(30)\frac{\mathcal E(\mathcal F)+\beta_{\mathcal F}\log L}{L} \le\frac{C_*+\log L}{L}. \tag{30}

At Y=LX+bY=LX+b, with θ=b/L∈[0,1)\theta=b/L\in[0,1),

0≤1LHBF(X)−HLBF+b(Y)≤1L∑n≥1(1n−1n+1)=1L.0\le \frac1L H_{B_{\mathcal F}}(X) -H_{LB_{\mathcal F}+b}(Y) \le\frac1L\sum_{n\ge1} \left(\frac1n-\frac1{n+1}\right)=\frac1L.

Also HY−HX≤log⁡(Y/X)≤log⁡L+1H_Y-H_X\le\log(Y/X)\le\log L+1. Consequently

HLBF+b(Y)−βFLHY≥DF(X)−log⁡L−2L.(31)H_{LB_{\mathcal F}+b}(Y)-\frac{\beta_{\mathcal F}}L H_Y \ge\frac{D_{\mathcal F}(X)-\log L-2}{L}. \tag{31}

Induction and protection of earlier cutoffs

Suppose the first j−1j-1 blocks and increasing cutoffs YiY_i have been chosen. Their finite delayed union B<jB_{<j}, of footprint β<j\beta_{<j}, has a bounded harmonic discrepancy: for a finite constant Cj−1C_{j-1},

HB<j(N)−β<jHN≥−Cj−1(N≥1).(32)H_{B_{<j}}(N)-\beta_{<j}H_N\ge-C_{j-1}\qquad(N\ge1). \tag{32}

This follows from periodic partial summation and the finitely many activation exceptions. Use C0=0C_0=0 for the empty prefix.

Choose LjL_j, a multiple of the old period, sufficiently large that

Lj>Yj−1(j>1),Lj−1≤2−j−3,(C∗+log⁡Lj)/Lj≤2−j,Lj−1≤2−j/HYi(1≤i<j).(33)\begin{gathered} L_j>Y_{j-1}\quad(j>1),\qquad L_j^{-1}\le2^{-j-3},\qquad (C_*+\log L_j)/L_j\le2^{-j},\\ L_j^{-1}\le2^{-j}/H_{Y_i}\qquad(1\le i<j). \end{gathered} \tag{33}

The old footprint is below 1/41/4, so an old surviving residue bjb_j exists. Apply (28) with

DFj(Xj)>Lj(j+Cj−1+3)+log⁡Lj+2,D_{\mathcal F_j}(X_j)> L_j(j+C_{j-1}+3)+\log L_j+2,

lift by (29), and put Yj=LjXj+bjY_j=L_jX_j+b_j. Each new modulus is at least Lj>Yj−1L_j>Y_{j-1}, whereas all old moduli are at most Yj−1Y_{j-1}. Thus the global moduli are distinct and strictly ordered block by block. Their full block unions are disjoint. Equations (31)--(32) give

HB≤j(Yj)−β≤jHYj>j+3.(34)H_{B_{\le j}}(Y_j)-\beta_{\le j}H_{Y_j}>j+3. \tag{34}

In the resulting infinite family,

β=∑jβFjLj<14,∑qeqlog⁡q=∑jE(Fj)+βFjlog⁡LjLj≤∑j2−j<∞.\beta=\sum_j\frac{\beta_{\mathcal F_j}}{L_j}<\frac14, \qquad \sum_qe_q\log q =\sum_j\frac{\mathcal E(\mathcal F_j) +\beta_{\mathcal F_j}\log L_j}{L_j} \le\sum_j2^{-j}<\infty.

Future moduli exceed YjY_j, so none changes deletion below that cutoff. Their future Haar cost is controlled as well:

(β−β≤j)HYj≤HYj∑k>jLk−1≤∑k>j2−k=2−j.(\beta-\beta_{\le j})H_{Y_j} \le H_{Y_j}\sum_{k>j}L_k^{-1} \le\sum_{k>j}2^{-k}=2^{-j}.

Equation (34) therefore gives HB(Yj)−βHYj>j+3−2−jH_B(Y_j)-\beta H_{Y_j}>j+3-2^{-j}.

Finally, the whole delayed block jj lies in {Ljn+bj:n≥1}\{L_jn+b_j:n\ge1\}, with at most N/LjN/L_j points below NN. Hence

∣(B∖B≤J)∩[1,N]∣≤N∑j>JLj−1.|(B\setminus B_{\le J})\cap[1,N]| \le N\sum_{j>J}L_j^{-1}.

Finite-prefix periodicity and this summable tail prove d(B)=βd(B)=\beta. This completes (27), including original activation and natural-density existence. Preparations can thus be repeated with summable density and energy cost while producing indefinitely increasing additive spikes. Only a normalized, sublogarithmic estimate could settle the original problem; the present construction neither supplies nor refutes it.